l4nsky's Methodology

[l4nsky]

DISCLAIMER: I’m fully aware that at some point in time, someone will make a comment in this thread saying my methods are excessive, complicated, exceedingly complex, not necessary, serve no purpose other than adding difficulty, and would ruin the hobby for them if they followed my path. In this, we can partially agree. These ideas, theories, and methods for husbandry are not for everyone and I fully admit and agree that some are not necessary in the slightest. Tarantulas and other animals can be maintained, cared for, and bred successfully with far simpler and basic methods. You are not witnessing an individual saying all of this is necessary to be a passionate, dedicated, ethical, and knowledgeable keeper of arachnids and their ilk or that all of this is required to enjoy the hobby. You are witnessing an individual that is merging together and sharing several passion hobbies (zoology, animal husbandry, research and development, computer programming, technology, data analysis, and engineering) for the purpose of my own personal enjoyment of the hobby, the advancement of captive husbandry, knowledge, conservation through commercialization, and the inspiration of other like-minded and/or similarly skilled hobbyists to think outside of the box and push the status quo of generally accepted methodologies (just because it works doesn’t mean it can’t be improved). There may be errors in my theories, my understanding of certain concepts, and the methods I take to achieve results. I welcome all constructive criticism and view said criticisms positively, as the intentions of the observer making them are to advance my own knowledge through education and possibly ensure the animals in my collection are receiving the best care possible.

Hola,

My name is Matt and I am a tarantula keeper (among other things) with a particular interest in arboreal and Asian species. I’ve been keeping inverts since Feb 2017 (still a youngster as compared to the many Old Timers here who have been shaping the hobby for decades). I have had a lifelong passion for zoology with a specific interest in predatory animals. I have been a field herper since I could walk and have kept reptiles and amphibians off and on my whole life. I have kept and maintained aquariums and fish of various sizes for two decades. I was a moderator and then a global moderator for the now deceased predatory fish forum Aquatic Predators before I even had a driver’s license. I have a passion for mycology and the patience and extremely high level of detail required for this hobby has filtered over to all of my other endeavors. I have an interest in carnivorous plants as well, but I am still a neophyte in that hobby. I program in Python and perform data analysis as part of my job for my current employer, as well as use the language to develop personal projects.

So, why create this thread? Well, there are a few reasons. Like other individuals that have a myriad of hobbies, I have found that the skills acquired from one can easily crossover to others and offer new insights and advancements that would otherwise not be possible. This thread is for the purpose of sharing those insights, advancements, and methodologies. Arachnoboards has been an amazing source of information for me and has provided an incalculable wealth of data points that have helped me shape and solidify my methodology. I have stood on the shoulders of giants like @grayzone, @boina, @JoeRossi, @cold blood, @viper69, @AphonopelmaTX, and many, many, many more. In homage to those who have contributed before me, I have made this thread to potentially be just as helpful and to provide a starting point to both new keepers with no experience and advanced keepers alike who want to take their hobby to the next level. Also, this thread will share some of my experimental, and as of yet, unproven methods I’m developing and they will be marked as such until validated or disproven. I will also include the data around these projects and the results of the experiments run using them. The purpose of sharing the more experimental techniques is to possibly encourage others to try them and to potentially crowdsource ideas and improvements around the methods. Finally, the last purpose of this thread is to inspire and encourage other successful keepers to post their own methodology threads in detail to provide time-tested, successful strategies for various species in order to combat all of the erroneous information that is posted as various care sheets or articles on the net. We, as a community, should pool together our knowledge and experience in order to suss out the best husbandry methodologies. Holding that information back because of elitism, fear of criticism, or contempt due to perceived slights helps no one and only serves to harm the animals we have chosen to keep and care for in captive confines.

So, without further ado (and run-on sentences), let’s get started.

Thanks,
--Matt

 

[l4nsky]

General and Species-Specific Methods and Theories​

This post will detail the general theories and practices I base my version of husbandry on as well offer species-specific methods of husbandry for those few that I keep where my version of husbandry differs from the generally accepted methods. The following posts will use these general notes to expand off of when setting up these enclosures.

On the Topic of Substrate​

The standard substrate mixture I use is the following mix by volume:

• 2 parts Zoo Med Reptisoil
• 2 parts dry, loose Zoo Med Eco Earth
• 1 part dry sphagnum moss
• 1 part vermiculite

I have found this mixture to retain moisture extremely well as well as being able to compact tightly and support extensive burrowing with no risk of collapse when compact. I use this substrate almost exclusively and I’ll mix up large amounts of this to store in plastic storage totes. Unless otherwise noted, I will use this substrate mix in all the enclosure setups in this list of methods.

 

[l4nsky]

Mainstay Enclosures for Arboreals​

My main interest in this hobby is arboreal tarantulas (don’t ask me why as I don’t have one defining reason). The following design was my first R&D dive into tarantula husbandry and has stayed consistent, with few changes. My criteria for these enclosures, in no particular order, were the following:

• Extremely versatile: These enclosures had to be able to raise every arboreal, whether it was an Aviculariinae sp. or an Ornithotoninae sp.
• Good visibility: Clear was mandatory. I wanted to make sure I could more easily see the inhabitants to check their health as they would grow. Honestly, I also wanted to just see the tarantulas in their full color and detail as that’s one of the joys of this hobby.
• Easily Available: I needed to be able to consistently find them available for sale on a moment’s notice. You never know when you’ll get the opportunity to acquire something special.
• Durable: Glass was obviously out. The enclosure also had to be able to be cleaned multiple times and reused, as well as survive a fall in the worst-case scenario.
• Secure: When closed, the enclosure had to be completely secure. Consequently, it should also be obvious and easily visible that it isn’t secure (horizontally mounted clasp locks are out)
• Cheap: These will be temporary/grow-out enclosures for the most part. I couldn’t justify spending more than $10 each (acrylic is out), especially when I could use that extra money for a better adult enclosure. Also, if one becomes damaged and needs to be replaced, they need to be able to be replaced without spending the money a decent sling would cost.
• Easily Modified: Enclosure had to be easily modified for ventilation. This modification had to be able to be done quickly as well as have little chance to destroy the enclosure (ex cracking the material).
• Ascetics: They had to look good on a shelf. Function is obviously more important than form, but if you can accomplish both without sacrificing either, than it’s that much better. After all, part of the joy of having any collection is in how you display it.

It was a tall order to find something that would actually meet all of these parameters, but in the end, I believe I did. Through research here on the boards and a trip to Walmart, I discovered the ubiquitous “Mainstay Enclosures”. More formally, they are sold by Walmart as Mainstay Food Storage Containers.

• They’re available as ½ gallon and gallon sizes at most of the brick and mortar stores I’ve been to (Easily Available, I have 3 Walmart’s within 30 mins from me).
• They are relatively cheap as well, costing less than $5 each (Cheap, especially for all that they are capable of really).
• They are screw top enclosures (Secure when closed, yet easy to see if the lid is cocked open and not secured in some way).
• They are clear, standardized in appearance, and not completely unattractive (Check the Ascetics and Good Visibility requirements off the list)
• They are made of a relatively thick plastic that is pretty resistant to cracking yet melts like butter under a soldering iron (Durable and Easily Modified. A soldering iron makes the task of adding ventilation a breeze. Also, the enclosure is still able to survive a fall if the worst should happen).

The last requirement (Extremely Versatile) was all dependent on the placement and quantity of ventilation holes as well as the décor placement (substrate etc) inside. The criteria to be able to house either a Caribena versicolor or a Omothymus violaceopes utilizing the same type of enclosure made this a tall order. To check this requirement required a little more research and experimentation. In the end, I came up with following design:





Regardless of the size of the enclosure, the ventilation stays roughly the same. On each side, starting at the top of the molded in grip and ending at the bottom of the same grip, a 4 x 7 or 4 x 8 grid of ventilation holes are melted into each side (for a total of 28-32 ventilation holes per side). On the lid of the enclosure, a 3 x 3 grid of holes the same size is melted into the center of the lid. That’s it, simple and easy but the design offers several advantages that I’ll explain throughout this write up. However, there is one particular piece of physics this enclosure was designed to take advantage of. That is the stack, or chimney effect.

In ELI5 terms, if the air inside a container is warmer than the air outside the container, the enclosed air will rise. As it does, and if it can escape the enclosure, it will suck in cooler air from lower ventilation points (nature abhors a vacuum). By restricting the top flow in comparison to the cross flow, we can maintain a stable temperature and humidity inside the enclosure while still maintaining optimum air flow. I created a simple visualization as seen below.



Now the astute among you probably noticed that heat is introduced to the enclosure from the bottom in the visualization. For these setups, I do use indirect, gentle, supplemental heat. Currently I accomplish this by keeping these enclosures on top of my lizard enclosure (as seen below). In the future, I’ll have to find a similar method, (potentially I’d have shallow heated boxes on a shelf system to achieve the same effect). It usually only raises the temperature a few degrees above ambient (to roughly 76 degrees Fahrenheit in the winter and 82 degrees in the summer). The goal here is to make a small change to increase ventilation via the stack effect, not bump the enclosure temperature up by 10 degrees. IMPORTANT NOTE: NEVER USE AN UNREGULATED HEATING ELEMENT (Ex a heat pad without a thermostat) AND NEVER ALLOW A TARANTULA TO COME WITHIN AN INCH OF A HEATNG ELEMENT. IN DOING SO, YOU HAVE A STRONG POSSIBILITY OF KILLING YOUR TARANTULA!



I realize a lot of keepers are scared away from offering specific heat and opt for more general heat like a heated outer enclosure or heating the room itself. I understand why, using specific heating can have fatal results if not used correctly (Direct contact between the heating element and the enclosure can kill a tarantula). For my collection, utilizing this setup, enclosures and type of heating, the risks are easily mitigated and the rewards are numerous. For one, I’d rather allow my adults to experience the seasonal temperature difference without having to keep multiple rooms at different temperatures and be able to independently modify their enclosure environment parameters if they are in a breeding cycle. Also, by heating an entire area, you reduce the temperature ratio between the enclosed air and the outside air, reducing the amount of air turnover and ventilation in the enclosure from the stack effect. Lastly, the indirect heat from the bottom paired with a deeper substrate, makes it really easy to judge and maintain proper soil moisture stratification and maintain the proper humidity for the desired species. That’s a tall claim, as it’s one of the main struggles for people that keep both species that require a lower humidity/soil moisture level like Avicularia and a higher humidity/soil moisture level like Phormingochilus. How can indirect heating help maintain both types of husbandry parameters in one enclosure design? I’ll explain using moisture dependent species as an example and touch on the implications for species that require less moisture a bit later in enclosure setup.



DISCLAIMER: The Enclosure above was taken off heat for this picture. As the air inside started to cool, condensation started to form in the sphagnum moss buried towards the rear of the enclosure. On heat, this condensation is not there.

The above enclosure houses a subadult female Phormingochilus sp. Akcaya. As you can see, she has a deep substrate. Originally, the substrate was only covering the bottom 2 rows of ventilation, but her burrow spoil was piled up past that point (there has been a time or two where I’ve had to remove some soil to ensure adequate ventilation. In fact, some substrate was removed from this enclosure shortly after this picture when the female expanded her burrow further). You can see that even though the ventilation holes are covered in dirt, the stack effect can still pull in outside air from the buried ventilation holes. Since this air is drier than the soil, it pulls moisture from the soil as it rises. This increases the air humidity, but since the air turnover is increased from the stack effect, it prevents stagnate conditions which can be deadly. This can be a double-edged sword however, as increased air turnover means the enclosure will dry out faster. This is why a deep substrate is necessary. It holds more moisture and can maintain a stable environment for a longer time. The astute observer will also notice that the soil at the front of the enclosure has more moisture than the center. This is because when I add moisture to the soil, I aim a spray bottle on the inside of the front. This prevents water from running out the ventilation holes and since the enclosure is clear, I can see the water percolate down to the bottom layer. Speaking of the bottom layer, you’ll notice that because of the specific placement of the ventilation holes in relation to the molded in grip, the bottom portion of the enclosure retains moisture the longest since it lacks ventilation. Also, the distance between the bottom ventilation hole and the bottom of the enclosure is greater than or equal to the height of any sized tarantula that will be kept inside. This ensures that they will be able to make a full burrow all the way at the bottom, in the moistest area should they want to. All of these features allow me to easily maintain proper soil moisture stratification, but there is another feature of the indirect heat/Mainstay enclosures strategy that makes it easier to judge soil moisture. The corners at the bottom of the enclosure turn inward, creating a sort of “overhang” at the bottom. Try as you might, when your packing soil down, there are usually small air gaps under this ledge. In these small gaps, due to the supplemental heat from the bottom, heated air will get trapped under the ledge. As that trapped air cools, condensation will form, as seen below:



DISCLAIMER: This picture was taken of a newly setup enclosure recently pulled off of heat. This amount of condensation in a newly setup enclosure with a décor setup designed for a moisture dependent species is expected. This amount of condensation in a new enclosure usually vanishes after 2 days on heat (I give more reasoning on this a little further on). The condensation displayed here is a bit excessive, but it was the only way to get a picture that clearly shows the effect. In practice, the condensation will be hardly visible and you’ll have to closely inspect these air pockets to see the microdroplets.

Once again, this picture is to show the effect. You don’t want to see this amount of condensation at all in enclosures for moisture dependent species that have been setup for at least a few days or in enclosures designed for non moisture dependent tarantulas. If you do, you’re overwatering. You should barely see a few micro droplets spread out in the air pockets under the overhang (more for moisture dependent species, less if any for non moisture dependent species). You can use the presence or absence of these micro droplets to better gauge the soil moisture level in the deepest layers of substrate. The higher up the side of the enclosure you go, there should be little to no condensation as well. This realization really helped me become established at keeping moisture dependent species, as the difference in soil color can be extremely subtle and hard to notice without having prior experience or directly comparing it to dry soil. Nowadays, I can use the weight of the enclosure to identify those I need to look closer at to judge the soil moisture levels. Being able to properly judge soil moisture levels is definitely an acquired skill, but this little trick allowed me to lessen the learning curve.

In general, I will use a half gallon Mainstay for slings larger than 1" DLS up to 2" or 2.5" DLS. I will use the gallon Mainstays for juveniles between 2" DLS up to 4.5" DLS.

 

[l4nsky]

General Mainstay Enclosure Décor Setup​

In general, and with few exceptions, for these enclosures, I will always use a deeper substrate than what most keepers will recommend. A deeper substrate holds more moisture and can keep the internal humidity levels stable. I will also setup a new enclosure with a soil moisture gradient straight off the bat by dividing the planned soil depth into thirds and using an increasingly drier substrate mix for the upper portions. I will also use cork bark flats or half rounds (never full rounds as I want to maintain visibility on the growing tarantulas to assess their health), at least one large fake leaf, dry sphagnum moss, and a water dish in all enclosures. Aside from all these commonalities, the enclosure setups are geared specifically towards their intended inhabitants and the general methods are further tailored to create specific methods for those inhabitants.

Mainstay Enclosure Décor Setup for Moisture Dependent Species​

The pictures above are of my standard Half Gallon Mainstay Enclosure with a setup geared towards moisture dependent species, specifically Asian Arboreals. The same setup is utilized in gallon sized Mainstays as well, with the obvious adjustments to compensate for the enclosure size difference. We’ll start with the most important aspect of the enclosure, and that is the substrate depth.

• For Half Gallon Mainstays, the substrate depth should be enough to cover the 3 bottom rows of side ventilation holes. This is roughly 2.5” of substrate.
• For Gallon Mainstays, the substrate depth should be enough to cover the bottom 2 rows of side ventilation holes. This is roughly 3.25” of substrate.

The tarantulas kept in the Half Gallons are usually younger and more prone to desiccation due to a less developed waxy cuticle. It’s for this reason I like to add more substrate, bury more ventilation holes, and restrict the airflow a bit more (Increased ambient humidity while still maintaining suitable air turnover). Those tarantulas kept in the Gallons are usually hardier with their increased size and benefit from a little more room to spread their legs when they grow.

The tarantula will likely cover up additional ventilation while digging a burrow, but this burrow spoil is loose and breathes well. Generally, I have found that a few additional rows covered up with this loose substrate doesn’t have any perceptible negative effect. Having said that, there are a few points where I will remove this substrate as well. If I see condensation forming under the upper ledge of the enclosure, I will immediately remove the substrate until only 3 rows of ventilation are buried on both sides (Half Gallon or Gallon). Condensation on the upper ledge of the enclosure is indicative of too much soil moisture and a lack of ventilation for the heat level you’re using. Removing some substrate should immediately solve this problem, as you’re both increasing ventilation and removing some of the water bearing soil. If you still have condensation a few hours after this fix, you’re either watering way too much and/or you’re using too much heat. Both of these actions should be closely examined to find the flaw in your husbandry skills and correct it. Also, if I don’t have at least 6 open rows of ventilation cumulatively between both sides of the enclosure with at least 2 rows of ventilation open on one side, I will remove the substrate until only 3 rows of ventilation are buried on both sides (Half Gallon or Gallon).

As stated in the beginning, I generally establish a soil moisture gradient during the initial setup. To do this, I evenly divide the intended soil depth into 3 even segments.

• For Half Gallon Mainstays, this means that each soil moisture layer should be laid down so that it’s roughly 0.833 inches deep.
• For Gallon Mainstays, this means that each soil moisture layer should be laid down so that it’s roughly 1.083 inches deep.

Seriously though, I’m not going to be that specific as to break out a tape measure for each layer. I know where I want the soil level to be for each enclosure in relation to the side ventilation holes and I will eyeball that distance and break it down into roughly even thirds.

Alright, I need to break off on a little bit of a tangent here and discuss the subject of field capacity in relation to mycology. Now field capacity is technically defined as the water content of a soil after gravitational drainage over approximately a day. Basically how much water could the substrate hold in it’s unaltered, natural state. For growing mycelium, we’ve found that the ideal field capacity is roughly 60%. A quick dirty trick to get this right in mycology is to squeeze (and I mean SQUEEZE) a handful of substrate. If only one or two drops comes out of your clenched fist, this should be really close to 60%. If you’re ever in doubt, always err on the side of drier as well. It’s a lot harder to take moisture out then it is to add moisture to a substrate. Going forward, proper field capacity will be defined as squeezing the substrate hard and only having one or two drops come out of your clenched fist.

Back to the setup. For the bottom layer of substrate, you should use substrate that has proper field capacity. To achieve this, start out with a big bowl of dry substrate, distilled or R/O water, and a mixing implement. Add water and stir the substrate until all the water has been absorbed. Grab a handful and squeeze it hard. If more than 1 or two drops drips from your clenched fist of substrate, crumble the substrate in your hand back into the bowl, add a handful of dry substrate, thoroughly remix, and test again. If it’s still too wet, repeat until you get the desired results. If the substrate is too dry, you get no water droplets out of a clenched fist of substrate, or your hands aren’t damp after you squeeze the substrate, crumble the clenched fist of substrate in your hand back into the bowl, add a little bit of water, thoroughly remix, and test again. If it’s still to dry, repeat until you get the desired results. Once you have the substrate to a proper field capacity, add this to the enclosure as the bottom layer of substrate. Use your fist to ensure that this layer is well compacted. We want to do this to maintain and support future burrow construction and reduce the size of the air pockets in the soil to lessen evaporation to ensure the bottom layer retains moisture.

For the 2nd of the 3 layers, I will take a bowl of substrate at proper field capacity and add roughly 10% by volume of dry substrate and thoroughly mix it in. I will add this substrate as my second layer, packing it down with my fist the same as before. By this layer, the substrate will be past the bottom internal ledge of the enclosure (mentioned earlier when discussing using condensation from indirect heating to judge the soil moisture level of the bottom level of substrate). Make sure that you do still have some small air gaps under this ledge so you can use the microdroplets of condensation to judge soil moisture levels. If not, now would be the time to correct this.

It’s at the second layer of substrate that I will embed a cork bark flat or half round. For Asians, as they will typically make large burrows, I will use a piece of cork bark that tapers up to the top (wider at the bottom then the top) and lean it against the back of the enclosure at an angle between 60 and 75 degrees. The cork bark should be an inch or two from the top corner aka the ledge of the enclosure when it is in this position. I will bury the bottom of the cork bark roughly half way into the second layer as well. This angle of the cork bark and wider bottom allows the tarantula to excavate a larger “atrium” behind the cork bark before burrowing down into the deeper substrate. They will often stash their molts here in this atrium, making them easier to retrieve for sexing. Before continuing onto the next layer of substrate, make sure the tarantula will be able to get behind the cork bark either from the side or from the top after the final layer of substrate is added. If it won’t, take the time now to adjust your cork bark or find another piece to use.

For the final third layer, I will take a bowl of substrate at proper field capacity and add roughly 20% by volume of the dry substrate (if you have soil left over from the 2nd of the 3 layers, simply judge the overall volume of the leftover soil and add roughly 10% of that volume to the bowl and thoroughly mix it in). This soil should be added in and packed down with your fist or knuckles just like before. Make sure to add the proper amount of soil behind the cork bark as well (don’t worry if you can’t get this is as compacted as the rest of the soil, it will, in all likelihood, be excavated shortly). At this time, I will also take some soil and build a small mound at the base of the cork bark, packing it in tightly to secure the cork bark in place. By the end of this, the soil height should be covering the correct amount of ventilation holes for the size of enclosure as listed above.

It’s at this point, I’ll add the final touches. I’ll fill approximately 60% of the volume behind the cork bark with loose sphagnum moss to provide a hiding spot immediately after rehousing and for future use in dirt curtains. I’ll also add one large, fake, plastic leaf by pushing the stem of the leaf into the substrate of a back corner of the enclosure. This will also provide a hiding spot immediately after a rehouse to reduce the risk of bolting as well as provide anchoring points should the tarantula choose not to make its burrow behind the cork bark. Finally, I will add a water bowl of the appropriate size for the enclosure and its complete.

When a newly setup enclosure of this design is placed on heat, it’s normal to have increased condensation in the air pockets under the lower ledge. The larger amounts of condensation should disappear in a few days. If it doesn’t you’ve either used a soil with a field capacity that was too high or you’re using too much heat. You will need to examine both actions and adjust accordingly going forward. You may have to deal with mold issues in the future due to this excess moisture from the start as well.

Mainstay Enclosure Décor Setup for Non Moisture Dependent Species​

DISCLAIMER: As of this writing (3/14/2021), even though these enclosures were designed with them in mind, I haven’t kept any Avicularia sp. in these enclosures as I am just now circling back to NW Arboreals. I have kept several Poecilotheria sp. as well as a Psalmopoeus sp. using the following setup and I have observed that the setup does keep a lower ambient humidity and can dry out quickly from an accidental overwatering. I’m confident that I will be able to successfully raise Avicularia sp. using this design and setup, however I’m marking it as EXPERIMENTAL FOR AVICULARIA until I can verify this first hand.



The pictures above are of my standard Gallon Mainstay Enclosure with a setup geared towards non moisture dependent species, like Psalmopoeus, Poecilotheria, and Avicularia species. The same setup is utilized in half gallon sized Mainstays as well, with the obvious adjustments to compensate for the enclosure size difference. We’ll start with the most important aspect of the enclosure, and that is the substrate depth. Unlike the setup for moisture dependent species, this setup maintains the same amount of ventilation holes covered regardless of the size of the enclosure used (half gallon or gallon).

• The substrate depth should be enough to cover just one row of ventilation holes on both sides. For a half gallon, this is roughly 1.75”. For a gallon, this is roughly 2.5”.

The reason that I don’t cover more ventilation holes in the half gallon size for non-moisture dependent species in comparison to the enclosures for moisture dependent species is that I’ve found the non-moisture dependent species are more resistant to desiccation at small sizes compared to moisture dependent species at the same size. Its for this reason that I prefer increased ventilation, as high humidity isn’t the goal for these specimens.

Even though there is less substrate depth with these enclosures I will still start out a new setup with an established soil moisture gradient using a similar technique as described in detail earlier when discussing the moisture dependent species setup. To do this, I will evenly divide the intended soil depth into 3 even segments.

• For Half Gallon Mainstays, this means each soil moisture layer should be laid down so that it’s roughly 0.5833” deep.
• For Gallon Mainstays, this means that each soil moisture layer should be laid down so that it’s roughly 0.833 inches deep.

Once again, I’m not breaking out the micrometer to ensure the depth of the soil moisture layer is in spec, I’m eyeballing it using the dimensions between the bottom of the enclosure and the top of the bottom row of ventilation holes and dividing by three.

For the bottom layer of substrate, I will use a layer of substrate that is just below proper field capacity (as defined in the section regarding moisture dependent species setup). When I strongly squeeze a handful of the substrate, I don’t want to see any drops of moisture come out of my clenched fist of substrate, but I do want my hands to feel moist after I have squeezed the substrate. If you have too much or too little moisture in your substrate, refer to the steps listed in the section on moisture dependent species to address this issue before continuing. Once you have the substrate properly prepared, place it into the bottom of the enclosure and pack it down tightly with your fist. We want to do this to decrease the size of the air pockets in this layer to retain moisture.

It’s at this stage, I will add the cork bark to the enclosure. Since the inhabitants of this enclosure design won’t be burrowing as extensively as moisture dependent species (thus not needing as much space to burrow under/behind the cork bark) and since the soil depth is shallower, we want to get the cork bark in place now to better secure it. I will use a straight or tapering upwards piece of flat or half round cork bark, leaned against the back of the enclosure at an angle between 75 and 85 degrees. The cork bark should be an inch or two from the top corner aka the ledge of the enclosure when it is in this position. At this point, make sure the tarantula will be able to get behind the cork bark from the top. If it won’t, take the time now to adjust your cork bark or find another piece to use.

For the 2nd of the 3 layers, I will take a bowl full of soil that has the same field capacity as the bottom layer and add 10% by volume of dry soil to the mixture and thoroughly mix it in. I will add this soil for the second layer and use my fists to pack it down just like the first layer, taking care to pack the soil around the base of the cork bark. Don’t worry if you can’t get the same soil compression behind the piece of cork bark, just make sure you get some compression. By this layer, the substrate will be past the bottom internal ledge of the enclosure (mentioned earlier when discussing using condensation from indirect heating to judge the soil moisture level of the bottom level of substrate). Make sure that you do still have some small air gaps under this ledge so you can use the microdroplets of condensation to judge soil moisture levels. If not, now would be the time to correct this.

For the final third layer, I will start with a bowl full of soil that has the same field capacity as the bottom layer and add roughly 50% by volume of dry substrate. I will mound up this substrate around the base of the cork bark and use my fist or knuckles to tightly compact it for added stability. I will then add this soil LOOSE AND UNCOMPACTED to the desired depth. This last step with loose substrate is necessary. This layer of substrate, in addition to being significantly drier than the rest, is also fully ventilated as it covers the one row of ventilation holes. This ventilation combined with the loose substrate structure, ensures the top layer of substrate stays drier than those below it and dries out quickly after watering due to the increased surface area in the air pockets. The effect this has is a lower overall ambient humidity inside the enclosure and being able to quickly recover those levels after accidently overwatering the substrate. As the heated, moisture filled air slowly rises from the bottom, it will lose some of its moisture to the drier, loose layer of substrate and in turn, decrease the humidity being evaporated from the soil. It’s kind of a confusing concept to explain and grasp, but it works.

For the final touches, I’ll once again fill up roughly 60% of the volume of the cavity behind the cork bark with dry sphagnum moss for use in dirt curtains and as an initial hide after rehousing. I will also add a large piece of a plastic plant to create some clutter about 2/3rds the way up the enclosure. When viewed from the top, this plant should take up roughly 75% of the available space (meaning you should only be able to see 25% of the enclosure floor unobstructed). If at all possible, this plant should drape over the top of the cork bark as well without obstructing the tarantula from getting behind the cork bark. This will encourage the tarantula to use the cork bark for its hide and incorporate the plastic leaves into its hide, as well as provide an initial hiding spot immediately after a rehouse to reduce the chance of bolting. Finally, I will add a water bowl of the appropriate size for the enclosure and its complete.

In contrast to the moisture dependent species setup, when an enclosure of this setup is placed on heat, you should see minimal, if any, condensation form under the bottom ledge. If you do, you’ve either used a soil with a field capacity that was too high or you’re using too much heat. You will need to examine both actions and adjust accordingly going forward. You may have to deal with mold issues in the future due to this excess moisture from the start as well.

In Conclusion​

The methods detailed here have worked extremely well for me and I’ve never experienced a loss that can be directly correlated to improper heat, ambient humidity, or stagnant conditions caused by a lack of ventilation. The directions I’ve listed out for these enclosures are detailed by design. Like in programming, the goal is to be as explicit as possible and not assume that the reader can accurately guess what is being implied. Implicit directions that leave a lot open to interpretation can have the negative effect of allowing one to veer off the designated course. When you’re coding or writing documentation, you always want to err on the side of explicit. It’s not to insult the reader’s intelligence or comprehension. It’s to ensure that the points are clearly understood in the same manner by all.

 

[l4nsky]

Reserved for l4nsky's Catch Cup System. A less detailed writeup can be found here: Reinventing the Catch Cup

 

[l4nsky]

Reserved for Functional Adult Arboreal Breeding Enclosures (EXPERIMENTAL)

 

[l4nsky]

Reserved for Display Adult Arboreal Breeding Enclosures (EXPERIMENTAL)

 

[l4nsky]

l4nsky's Incubator Design
​

DISCLAIMER: The following design is EXPERIMENTAL and positive results with the design have not been proven. This design and its benefits are theoretical at this point and are provided for a topic of discussion, inspiration for other creative hobbyists, and as a potential starting point for breeders who want to test a different design of incubator (If you fall into the latter category, feel free to DM me if you want more accurate specs to duplicate this design for yourself. Forewarning, I will only share these details if you agree to share the data/results from your experiments). Should you choose to use this as of yet untested design as an incubator, I take no responsibility for the results or potential failures. Once again, this design is EXPERIMENTAL and using it places all of the risk on your shoulders.

The purpose of an incubator is to maintain a stable environment to assist in the development of a young organism. The environmental parameters that we aim to keep stable are:

• Temperature
• Humidity
• Air exchange

All of these parameters are crucial to maintain inside a defined range to ensure the best odds for success, but there is a 4th environmental parameter that needs to be considered: Sterility. The same conditions that promote fast and successful development for tarantulas, reptiles, amphibians, etc are also highly conducive to the growth and proliferation of bacteria, mold, and fungi. These microorganisms, while beneficial in certain conditions (cycled aquariums, bioactive setups, etc), can be completely detrimental to the goal of successfully hatching and raising young organisms. We try to maintain sterility by starting with clean equipment, being vigilant at monitoring, cleaning and replacing dirty materials, and walking the fine line around air exchange. We try to restrict air exchange to the point of reducing the potential of introducing contaminants and maintaining a high humidity/temperature while still being able to maintain a high enough turnover to prevent stagnation and allow oxygen to reach the developing organism. It’s a pretty fine balancing act that revolves around one of the most fragile life stages of an organism and can be a source of frustration for both new and seasoned breeders.

Focusing in on tarantula incubators, there are two major designs that are utilized today. Not counting a mechanical mom (which is in a category of its own IMO) these are the nested deli cup method, and the larger humidity chamber (using either @robc / @louise f hammock setup or wet paper towels/16oz deli cups). I’ll go over each briefly and highlight the pro’s and con’s that I see in their design.

The nested deli cup method is the one I see most often used today. This involves using a 32 oz deli cup to hold some sort of moisture (wet paper towels, wet coco coir, or just plain water) and a 16 oz deli cup nested inside. The 16 oz deli cup will have major ventilation in the bottom of the cup, either by creating a multitude of ventilation holes or cutting off the bottom and replacing it with a nylon hammock. There will also be ventilation on the top of 16 oz deli cup, either in the form of a plastic lid with a varying amount of ventilation holes or a specialty lid with ventilation holes overlaid by a loosely knit fabric. Finally, the 32 oz deli cup will also have a few ventilation holes. With this design, the modified 16oz deli cup becomes a mini humidity chamber, allowing humid air to rise through the ventilated bottom and then being contained and restricted by the lesser ventilation of the top lid. The pro’s are easily seen. The design is cheap, proven, passive, and simple to construct. The con’s are a little bit harder to see. The amount of ventilation that is needed to maintain temperature and humidity levels in the appropriate range is highly dependent on where you live and the ambient conditions. If you live in a dry area, like the American SW, and you don’t have a dedicated T room with its own microclimate (regulated humidity and temperature), you will need less ventilation holes to maintain the appropriate humidity level. The opposite is true in more humid environments like the PNW or Florida. You will need more ventilation to reduce air stagnation and keep the humidity within an acceptable range. Even if a new breeder follows a step-by-step guide with the exact ventilation placement as the OP, if they don’t take the OP’s home climate into consideration, they can fail. Another con to this design is the small air volume in the humidity chamber. Since this is a passive design to maintain humidity and there is no active air exchange in the humidity chamber, these should be opened from time to time to swap out the air and to check on the developing organisms for progress and signs of a problem (contamination, bad/infertile eggs, etc). This act of exposing the developing organisms to open air can have the unintended effect of introducing contaminants.

The second most popular design IMO is the humidity chamber. This design uses a small plastic tote or kritter keeper to maintain a stable environment. The humidity source is either wet paper towels, wet coco coir, water gel, or a container of water. The eggs are then either kept in 16 oz deli cups lined with dry paper towels/coffee filters or on top of a nylon hammock suspended over the humidity source (usually a container of water à la the @robc or @louise f tutorial). Ventilation holes are then placed into the outer container. Once again, the pro’s are easily seen. Like the nested deli cup method, the pro’s include the design is simple to construct, cheap, proven, and passive. In addition to these, this method also has larger air volume, meaning it’s more resistant to stagnation and needs to be opened for air exchange much less often. The con’s are likewise similar. The amount of ventilation that is needed to maintain temperature and humidity levels in the appropriate range is highly dependent on where you live and the ambient conditions. This must be taken into consideration during construction and will need to be experimented with to find the right combination of cross and top ventilation. The larger air volume of this design, while being a pro, can also be a con. Larger air volumes take longer to reach the desired humidity/temperature levels after being exposed to room parameters.

There is another common con of these two designs if the humidity source isn’t straight water. Wet paper towels and coco coir, in addition to providing the moisture needed for disruptive microorganisms to grow, also provide a source of nutrition for those microorganisms, and a substrate to grow on. Just because you can’t see a bacteria or mold colony doesn’t mean that they aren’t there. Usually, by the time you see a colony, it’s in the stage of exponential growth and can quickly cause harm if not immediately addressed.

With all of this in mind, I started laying out the goals of my incubator design and the methods I might take to accomplish them. They are:

• Stable humidity levels that can be precisely dialed in without having to physically modify the incubator (ex add or block ventilation holes).
• Stable temperature levels that can be precisely dialed in without having to physically modify the incubator (ex add or block ventilation holes).
• Active air exchange that can be precisely dialed in without physical modifications while simultaneously reducing the contamination potential.
• Active contamination control and increased biosecurity.
• The ability to be a set-and-forget design that required minimal input from the breeder to maintain the correct microenvironment for development.
• Scalable design that can work for both an amateur breeder with one sack or a professional breeder that could be pulling multiple egg sacks a month.
• Easily integrated with a computer monitoring/control system for future proofing, better records/data for each species, and around the clock monitoring of the internal microclimate.

Once again, this is a tall order to fulfill and I wasn’t able to find anything comparable in the invert hobby to base my design on or build off of. At first, I was looking into using a nested deli cup with heated water. This would allow me to maintain the temperature and humidity while utilizing the stack effect (as discussed in my Mainstay Enclosures for Arboreals post) for a more active form of ventilation and air exchange. Unfortunately, this didn’t address the sterility requirement, and in fact could potentially make it worse with the heated environment and no active means of sterilization. Instead of completely scrapping the idea however, I saw that it could be built on. Ultimately, I ended up with the following design:




I call this design a reactor incubator. Right off the bat, you can tell that simple design/construction and cheap are not going to be pro’s for this design, but stay with me as I believe the actual pro’s far outweigh any initial difficulty or cost that are inherent with this design. This incubator incorporates a proven method for maintaining a stable humidity, which is that of a humidity reactor. Humidity reactors, essentially sealed enclosures that air is forced through and humidified, have been used in the hobby before (ex RobC’s Mechanical Mom tutorial) and I’ve used them in some simpler and earlier fruiting chamber constructions for mycology. This design builds off the humidity reactor and hybridizes it with the nested deli cup incubator design. There are a few key elements of the design. One is a large body of continuously sterilized and heated water for both a source of humidity and heat to the developing eggs/EWL’s/1i slings. To accomplish this, I’m utilizing an aquarium heater to keep the water temperature a constant 82 degrees. I’m also using a mini UV sterilizer with integrated pump to circulate and sterilize the water. The model I’m using circulates/sterilizes 66 GPH. Another key element is the individual, isolated incubation chambers. These are essentially 32 oz deli cups, with the bottoms removed, that are embedded in the top of the lid of the gasketed Sterilite tote. The bottoms of these deli cups extend an inch or so into the heated and sterilized water, essentially sealing these chambers off from one another with sterilized water and allowing individual control of some of the environmental parameters within independent of each other. The final key element of this design is active air exchange and positive air pressure to reduce contamination via an aquarium air pump. To see how all of these elements come together to meet the scope of this project, let’s break down how this incubator works, the potential benefits I see, and how I’m going to go about testing this design via experimentation.

Referring to the previously provided pictures, we’re going to start with the tote choice. The prototype is built using a Sterilite 32 qt gasketed tote. This is important as we are going to attempt to use positive pressure to prevent potential contaminants entering the container, so we need to attempt to make this as airtight as possible. The gasketed tote also drastically decreases evaporation. Four 32 oz deli cups with the bottoms removed are then embedded in the lid. The water level in the chamber is such that the bottom inch or so of these deli cups are under water (as seen below). The aquarium heater and the UV sterilizer are then placed into the water. The power cords for these devices are run through a carefully cut notch in the back lip of the tote (this is important to try and keep the container as air tight as possible). In addition, the water I’m using is R/O water to start as sterile as possible and to reduce the amount of total dissolved solids that could potentially provide nutrition to unwanted microorganisms.



Next, starting at the air pump and following the airline up the side of the incubator, we encounter a one-way check valve. Under pressure from the air pump, this valve stays open. When the air pump stops providing this pressure, the valve closes, preventing water from coming back up the line to the pump. This is standard issue for most aquarium air line systems. After the check valve, the airline then reaches the top of the incubator and enters the reactor chamber between the two right incubation chambers. This line then heads to the bottom of the tote and encircles the inside of the container three times. The airline is held in place by suction cups (these will be siliconed in place in the future as they have a tendency to pop off due to how the plastic flexes under the water pressure). In addition, there is an additional 8” of slack added to the length of airline that runs between the lid of the tote and the first suction cup at the bottom of the tote. This is to allow the lid to be opened and provide enough space to disconnect the interior air hose from the external air hose. The purpose of running roughly 12’ of airline along the interior of the reactor chamber is to heat the air (my original design didn’t include this and since I don’t keep a heated T room, I wasn’t able to get more than 4 degrees over ambient room temperature). The airline then leaves the reactor chamber in the bottom right corner of the lid (there is an additional 8” of airline between the last suction cup and the lid to allow access to the chamber to disconnect the lid). Immediately after exiting the reactor chamber, the airline splits into two direction. The right airline goes to a ball valve, circles in between the two right incubation chambers, and then reenters the reactor chamber in the middle of the lid. This airline has a large air stone on it that is approximately 4” underwater (as seen in the previous picture). Going forward, this leg of the airline will be referred to as the overflow line. Returning back to the airline split in the bottom right corner of the lid, the left airline goes to a ball valve before feeding into a 4-line manifold. The four airlines coming off the manifold then head to the middle of the lid where they reenter the reactor. Each airline then enters a separate incubation chamber. Once inside the incubation chamber, the airline then heads down, terminating in an air stone approximately 4” underwater (as seen in the previous picture). The length of the four airlines from the manifold to the air stones inside the incubation chambers are the same. The airline inside the incubation chambers is wrapped in stainless steel wire to provide rigidity and to center the air stone in the incubation chamber to ensure all of the air enters the incubation chamber instead of escaping to the large airspace in the reaction chamber (as seen in the picture below).



Inside these incubation chambers, we place an incubator pod as seen below.




These incubator pods are made out of two 32 oz deli cups that are cut so that they are flush at the bottom. The depth of these incubator pods is 3”. A piece of nylon pantyhose is then stretched and sandwiched between the two deli cups. The nylon pantyhose and the two deli cups are bonded together using super glue. A fabric ventilated lid is then added to this incubator pod to complete it. A paper towel or coffee filter can be added inside or the eggs can simply be laid out on the nylon hammock.

To calibrate the airflow to the individual incubation chambers, first the ball valve in the overflow line is completely closed and the ball valve in the airline to the manifold is completely open. This forces the full volume of the air from the air pump into the 4-line manifold. The ball valves on the manifold are then adjusted so that roughly the same amount of air is going to each incubation chamber. Once this is complete, the ball valve in the overflow line is slowly opened to reduce the air going to the manifold and reduce the aeration to the incubation chambers to the desired level. A special note here, if different levels of aeration are desired for individual pods, this needs to be addressed before opening the overflow line. If you attempt to say increase the airflow to one of the incubation chambers after opening the overflow line, the extra airflow will be “stolen” from one of the other incubation chambers (the air being supplied to the manifold doesn’t increase, it’s just redistributed).

 

[l4nsky]

l4nsky's Incubator Design (Cont'd)
​

Preliminary results suggest that I may have hit all of the requirements for this design. Using cheap and small temp/humidity gauges, I’ve measured the internal temperature of the pods at 80-81 degrees (while the water is set at 82 degrees and the ambient room temperature was 74 degrees). Humidity levels from these gauges have to be taken with a grain of salt as the gauges are not able to be calibrated and are notoriously inaccurate when measuring higher humidity levels. All I can say based on the humidity numbers and my own observations is that the incubation pods have a RH of at least 80% (Some of the gauges were reading as high as 95%). Active air exchange using heated, humid, and relatively sterile air is achieved by running the airline through the heated water before being pumped into each incubation chamber through 4” of continuously sterilized water. The 4” of water acts as a filter of sorts to remove mold spores, dirt, and bacterial endospores (this won’t remove all of the microorganisms, but in theory it should remove quite a bit. The planned experiments discussed a bit later should shed some light on how effective this really is). The airflow and humidity seem to be able to be regulated using the manifold (more air to an incubation chamber increases the water’s surface area, increasing the humidity. Admittedly, the increased size and quantity of bubbles created when attempting to bump the humidity of an individual incubation chamber can make the nylon hammock/paper towels damp from the spray generated when the bubbles pop and a 2” incubation pod may be needed to take advantage of this while still retaining a relatively dry surface for the eggs). Temperature can be controlled directly via the built-in thermostat on the aquarium heater. The UV sterilizer is actively ensuring the water reservoir in the reaction chamber is as clean as possible at all times, greatly minimizing any cross-contamination potential between the incubation chambers. Once dialed in, the incubator pod’s environmental parameters appear stable and don’t require manual air exchange via opening the lid. Further, this design is scalable (should the design prove out, I’m already looking at creating the second generation prototype using 6” PVC pipe and T connectors for modularity) and data logging sensors can be fitted quite easily into the lids of the incubation pods. The last part of this design has to do with the active air exchange and positive pressure. In theory, the air pressure is higher in the incubation pods due to the pumped in air and restricted top ventilation, which should prevent or minimize contaminants from entering the pod. In addition, the air being pumped into the main reactor chamber via the overflow line should produce the same effect if it’s sealed properly and the airflow is sufficient. It might be true that the amount of air being added is not enough to make a difference (the designed experiments should provide an answer for this claim), at which point I might consider a more powerful air pump and air stones that produce finer bubbles.

There are a few modifications I have to make to the prototype before I continue testing and a few pieces of gear I have to acquire for the experiments. First, I need to seal the 32 oz deli cups to the lid with a bead of silicone. I also have to seal around all of the entrance/exit holes where the airline goes in the reactor and incubation chambers with silicone as well. Also, now that I have the placement of the suction cups, these will be secured with silicone. Finally, I might silicone the power cords for the heater and UV sterilizer/pump where they enter the reactor chamber (I’m undecided on taking this more permanent step and it will ultimately be decided by the experiments). I also want to modify the lids to have a clear viewing window inside to check the health of the developing eggs/experimental petri dishes without opening the incubator pod and risking contamination. As far as the gear I’m waiting on, I ordered a temp/humidity logger that can be calibrated and a number of 60mm plastic petri dishes. I will need these for the following experiments.

All of the following experiments will use the two proven methods detailed earlier in this post as controls.

• Temp/Humidity will be logged over a period of a week to prove the environmental parameter stability and see what additional modifications need to be made should these parameters fall outside of the generally accepted range.
• Two sterile agar plates will be placed in each pod. One of the plates will be exposed to the open air, the other will be sealed with parafilm and act as a control. Microorganism colony counts will be taken over a week to determine the degree of sterility that can be maintained. At the end of this experiment, a sample of the reservoir water will be smeared across a sterile agar plate using a flame sterilized loop and the colonies will be counted after incubation to determine the sterility of the water.
• An agar plate with an active bacterial colony will be placed in one of the incubation pods. After a week, a flame sterilized loop will be used to take samples off small, hard surfaces that will be placed on the paper towels in the nylon hammock in all of the incubation chambers and from the water reservoir. These samples will be smeared onto sterile agar plates and colony counts will be taken after incubation.

I will update this post with results after these experiments have been performed.

 

[l4nsky]

Reserved for JARVIS for Tarantulas (DESIGN IN PROGRESS) & l4nsky's Modular Sling Care System (EXPERIMENTAL)

 

[l4nsky]

Reserved for Sterilite Enclosures for Terrestrials & Fossorials

 

[goliathusdavid]

Now THIS is a methodical approach. Given my personal experience working with Ts I prefer enclosures larger than this, often sticking to the more expensive glass or acrylic where I would use plastic for other inverts. Love your substrate mixture however. Thank you so much for sharing your methods, and for crediting some of the people who inspired them! I look forward to reading more

 

[Arachnophobphile]

Thanks for your contribution, very detailed information. How about that I'm not far from you just across the river.

 

[l4nsky]

Now THIS is a methodical approach. Given my personal experience working with Ts I prefer enclosures larger than this, often sticking to the more expensive glass or acrylic where I would use plastic for other inverts. Love your substrate mixture however. Thank you so much for sharing your methods, and for crediting some of the people who inspired them! I look forward to reading more

Thanks, I forgot to add what size enclosures I use depending on a tarantula's size (added to the end of the third post). Future updates will be spaced a few weeks apart depending on the time I have available to create them.

Thanks for your contribution, very detailed information. How about that I'm not far from you just across the river.

Thanks. Lol we're actually on the same side of the river. I'm just from STL and it's easier for people to place my location than if I said Alton, IL.

 

[sk063]

Thank you for having the determination to revive the boards, " I get it people are tired of answering the same questions time and again", Americans in particular want what they want right now! WTH is searching??? But seriously, Thank you, I'll keep two eyes on this as it moves forward.

 

[Arachnophobphile]

Thanks. Lol we're actually on the same side of the river. I'm just from STL and it's easier for people to place my location than if I said Alton, IL.

Yeah lol I do the same thing. We are pretty close I'm in Collinsville. <edit>

 

[viper69]

Appreciate the nod, and your contribution.

I’m most curious to read the experimental entires.

 

[Kibosh]

Thank you so much for this. This is the stuff that pushes the hobby and the research forward to a better place. Look forward to reading it in full this week.

I have a friend who is also an engineer that I play a lot of table top war games with. He is constantly doing in depth battle reports with very detailed graphics and displays. I love his complex break downs of games turn by turn, move by move of each of our choices, why we made them, and how to improve upon them, with accompanying statistics of course haha. For me it brings a greater understanding of the games and thus more enjoyment.

Never apologize for being too detailed.

Thanks again and keep it up.

 

[l4nsky]

3/22/2021: I've added my concept for a new incubator design and outlined the planned experimentation around the design.

 

[Finikan]

This is brilliant! Thank you for posting.