Cross Ventilation

[YungRasputin]

is this an actual thing which exists? like, i know it seems like the in thing now, particularly with Avic arboreals or C. versicolor to talk about or recommend “cross ventilated” enclosures but i am skeptical about the actual functioning and necessity thereof comparative to top ventilation - not that cross ventilation is bad just that i don’t really buy into what all people have said about it and the primary reason for this is: if there is no air circulation, no cross winds or breeze, etc then what benefit is it? what would be the point? and seeing as air moisture rises and that the species in question benefit from rising air moisture why wouldn’t top ventilation be of central focus?

like i’m kind of really feeling some sort of way about another group I’m in where someone is obviously upset about their T dying, desperately trying to figure out what went wrong and people are dog piling them about cross ventilation when i don’t think the specimen died because there wasn’t another row of useless side holes

 

[DomGom TheFather]

I don't think it's cut and dry.
Cross venting is a term that gets used a lot.
I think the term proper ventilation should replace it. Or maybe adequate ventilation?
It varies by species but an avic will do great in a kritter keeper and may die in a box with only a few rows on the sides.

 

[Yigzatoth]

Cross ventilation is mostly to prevent saturation and stagnant air.
There is always some sort of cross breeze, cold air vs hot air. If you allow the cold air to enter from bellow it will force the hot air up making a small current.

 

[Liquifin]

Cross ventilation is something I find that is somewhat important, but at the same time it is very tangible depending on how skilled a tarantula keeper really is and the specimen/species itself. I don't know how to put my finger on it, but Avics and Caribena, etc. don't need an excessive amount of ventilation to thrive, but rather a very good understanding of the species and individuals themselves. I've known and seen really good keepers place like 4-5 ventilation holes and their specimens are thriving really well.

It is recommended to have cross ventilation for beginners or intermediate tarantula keepers. It is just a way to be safe rather sorry when keeping them. But a person who has very good in-person experience with them can probably keep them with less ventilation if they have a solid understanding of them. This is just my opinion, so take this what you will.

 

[viper69]

is this an actual thing which exists? like, i know it seems like the in thing now, particularly with Avic arboreals or C. versicolor to talk about or recommend “cross ventilated” enclosures but i am skeptical about the actual functioning and necessity thereof comparative to top ventilation - not that cross ventilation is bad just that i don’t really buy into what all people have said about it and the primary reason for this is: if there is no air circulation, no cross winds or breeze, etc then what benefit is it? what would be the point? and seeing as air moisture rises and that the species in question benefit from rising air moisture why wouldn’t top ventilation be of central focus?

like i’m kind of really feeling some sort of way about another group I’m in where someone is obviously upset about their T dying, desperately trying to figure out what went wrong and people are dog piling them about cross ventilation when i don’t think the specimen died because there wasn’t another row of useless side holes

Cross venting evolved due to owners killing Avics because their setups were moist/stuffy air boxes. Stagnant air kills them. People were trying to keep mini-rain forests by soaking sub and/or misting heavily because they were chasing humidity values from "caresheets", notoriously full of factually WRONG info.

However, holes in the sides of tank walls are not necessary. Just look at all the glass cubes that EU has. The ExoTerra is modeled from this standard that has been used successfully for many decades But in both of those designs, air flows from the front, rises and goes out the top.

 

[Chris LXXIX]

Cross venting evolved due to owners killing Avics because their setups were moist/stuffy air boxes. Stagnant air kills them. People were trying to keep mini-rain forests by soaking sub and/or misting heavily because they were chasing humidity values from "caresheets", notoriously full of factually WRONG info.

Definitely.

However, holes in the sides of tank walls are not necessary. Just look at all the glass cubes that EU has. The ExoTerra is modeled from this standard that has been used successfully for many decades But in both of those designs, air flows from the front, rises and goes out the top.

I know that you like those old good European glass enclosures we use. Here's one of mine for your average arboreal. Front opening, top ventilation, and cheap as heck - not even $15 at the change. Why buy a more priced 'Exo'?

 

[YungRasputin]

Cross venting evolved due to owners killing Avics because their setups were moist/stuffy air boxes. Stagnant air kills them. People were trying to keep mini-rain forests by soaking sub and/or misting heavily because they were chasing humidity values from "caresheets", notoriously full of factually WRONG info.

yes

However, holes in the sides of tank walls are not necessary. Just look at all the glass cubes that EU has. The ExoTerra is modeled from this standard that has been used successfully for many decades But in both of those designs, air flows from the front, rises and goes out the top.

what you describe is my own bias in this conversation - i prefer those enclosures and it’s what i have my own A. avicularia in - i just wanted to take a closer look at the science and underlining logic behind the cross ventilation system (and see if i was wrong about the subject)

 

[Tarantuland]

Definitely.



I know that you like those old good European glass enclosures we use. Here's one of mine for your average arboreal. Front opening, top ventilation, and cheap as heck - not even $15 at the change. Why buy a more priced 'Exo'?

View attachment 398106

Start shipping these across the pond then. Even with shipping they're probably cheaper than exoterras

 

[Chris LXXIX]

Start shipping these across the pond then. Even with shipping they're probably cheaper than exoterras

I don't know why those glass enclosures never gained the U.S/American T's market favor. Probably (IMO) too much 'spartan' for the taste at a general level? After all, in the U.S originated those more elaborated, fancy looking, acrylic enclosures. Don't know why

You can order those enclosures from Poland, Germany etc online shops, anyway.

 

[viper69]

I don't know why those glass enclosures never gained the U.S/American T's market favor

Me neither, it isn't like we don't have glass!!!

Don't know why

Same here. One person really started these acrylic setups decades ago. However, why glass wasn't chosen is beyond me.

I know acrylics for the end-user are more expensive than glass over there, that too I am not sure why.

Only advantage of plastic- it's less mass.

 

[VaporRyder]

I have wondered the same thing and posted this:

I don’t believe that ‘side or lateral airflow’ is a thing in human domiciles without a significant breeze rushing through.

School me!

Alright, I was being jokingly flippant - due to the nature of the thread it was posted in - but I think it’s a good question.

Someone, I think it was @The Grym Reaper, posted a neat little diagram that I came across in another (much older) thread; of how warm air rises, drawing cool air in through the side vents, which in turn is drawn upwards as it warms. (Tried to find the post to quote but can’t).

Whilst this made sense in theory, I did wonder whether there was a sufficient thermal difference between the air inside and outside the tank (assuming room heating rather than enclosure heating) to make it true in reality.

I keep my pokies in enclosures with generous top ventilation only.

 

[Chris LXXIX]

I keep my pokies in enclosures with generous top ventilation only.

Uhm, like basically the 90% of European keepers

 

[Edan bandoot]

None of my enclosures have top ventilation, it loses moisture too fast in my experience.

But I do use cross ventilation to prevent stagnant air.

Tarantulas live in holes in the ground, and 99% of the time they don't care about stagnant air or ventilation. But it is helpful for us keepers by reducing mold/fungus growth and allowing us to recreate a natural substrate wet/dry cycle.

@AphonopelmaTX did some interesting testing, which you can read here.

Personally, I think the notion of stress is far over rated in this hobby. I think I am in the minority who think so, but I occasionally put some of my tarantulas through some situations that others may find horrendous for the sake of knowing the limits of what they are capable of. Nothing dangerous that would put any of my tarantulas in any real danger, of course, but some situations that would be considered stressful and avoided at all cost to avoid this so-called "stress."



An example of what I mean is by looking at what happens when you flood the container of a spiderling that comes from an arid climate. In one case I intentionally flooded the burrow of one of my Aphonopelma mooreae spiderlings to see what it would do. Turns out, it had a solution to that problem. When the burrow was completely flooded with water, it clinged to the top of the burrow upside down to escape the standing water. When the water was drained, it came down and resumed normal resting position. Until then, I never knew an Aphonopelma species had a strategy for a flooded burrow. Now I have some insight on how a wild tarantula from a desert would deal with an occasional down pour.



In another instance, I wanted to know how an adult tarantula would react by being housed in a small container with little ventilation. So I put my adult Euathlus sp. in a plastic shoebox style container with a small layer of soil and a 1 ounce condiment cup for water. I didn't drill any ventilation holes in the container to find out if there was already enough ventilation without adding more. Turned out that there were no adverse effects at all. That was several years ago and it is still housed in the same plastic shoebox with no ventilation holes. It eats and drinks and carries on like you would expect a healthy normal tarantula would; there is no mold or fungus growth; etc. The conclusion drawn from that experience was that high amounts of ventilation really isn't that necessary in housing.



We often times underestimate how much crap a tarantula can take without any observable adverse effects to its health and well being. I don't think everyone should be running experiments on their tarantulas, but to not try something just because it is thought a tarantula can't handle the stress is, in my opinion, ludicrous.

 

[VaporRyder]

None of my enclosures have top ventilation, it loses moisture too fast in my experience.

But I do use cross ventilation to prevent stagnant air.

Tarantulas live in holes in the ground, and 99% of the time they don't care about stagnant air or ventilation. But it is helpful for us keepers by reducing mold/fungus growth and allowing us to recreate a natural substrate wet/dry cycle.

@AphonopelmaTX did some interesting testing, which you can read here.

I use vermiculite mixed in with my substrate to aid moisture absorption and retention. It seems to work well.

 

[The Grym Reaper]

Someone, I think it was @The Grym Reaper, posted a neat little diagram that I came across in another (much older) thread; of how warm air rises, drawing cool air in through the side vents, which in turn is drawn upwards as it warms.

Yep, basically just made it to show how most European glass enclosures and Exo Terras function because people seem to think that you need to strafe every side of your enclosures with a minigun in order to have "adequate" ventilation which is absolutely not the case. All you really need to create sufficient air circulation is ventilation just above sub level on at least one side, and ventilation in the top/lid.

Whilst this made sense in theory, I did wonder whether there was a sufficient thermal difference between the air inside and outside the tank (assuming room heating rather than enclosure heating) to make it true in reality.

Even if you're not heating the enclosure directly there will still be some air exchange because the air in the room isn't ever really still. You breathe, you move, you have appliances (e.g. PC/fan/heater) running/generating heat, all of these things move air around one way or another.

 

[l4nsky]

Not only does heat rise and create air currents, but so does moist air (as it's less dense then dry air). I touched on this recently in the humidity thread.

On the Subject of Ventilation

Controlling ventilation and the air turnover rate directly controls humidity in tandem with soil moisture. Humid air rises and escapes from the top of the enclosure. Take advantage of that. For species that like it on the drier side, use more top ventilation then cross ventilation to allow the humidity to escape quickly. For those that need to be kept on the moist side, utilize more cross ventilation then top ventilation. Restricting the humid air from escaping through the top increases the ambient humidity in the enclosure, while the ample cross ventilation prevents stagnate conditions from forming.

https://arachnoboards.com/threads/the-paradoxical-importance-of-humidity.346451/post-3190549

 

[Dorifto]

Yep, basically just made it to show how most European glass enclosures and Exo Terras function because people seem to think that you need to strafe every side of your enclosures with a minigun in order to have "adequate" ventilation which is absolutely not the case. All you really need to create sufficient air circulation is ventilation just above sub level on at least one side, and ventilation in the top/lid.

View attachment 398117



Even if you're not heating the enclosure directly there will still be some air exchange because the air in the room isn't ever really still. You breathe, you move, you have appliances (e.g. PC/fan/heater) running/generating heat, all of these things move air around one way or another.

Thank you... you fck up my post hahahahaha, I was explaining the same

European style enclosures like mine and the same like the one you posted, work by convection, that's why they are good keeping a stable humidity levels. The heated air exits from the top vents, creating a low pressure on top, so the cold and drier air from the bottom tries to balance it, taking moisture from the substrate and raising it to the top again.

 

[Dorifto]

Not only does heat rise and create air currents, but so does moist air (as it's less dense then dry air). I touched on this recently in the humidity thread.


https://arachnoboards.com/threads/the-paradoxical-importance-of-humidity.346451/post-3190549

What? How I passed this thread?

My apologies!!!

 

[AphonopelmaTX]

Tarantulas live in holes in the ground, and 99% of the time they don't care about stagnant air or ventilation. But it is helpful for us keepers by reducing mold/fungus growth and allowing us to recreate a natural substrate wet/dry cycle.

The holes burrowing tarantulas make in nature are made in soils that are aerated and with good drainage so no, even they are not living in stagnant conditions. The aeration and drainage of the soil is due to the roots of vegetation, soil fauna such as earthworms, the properties of the soil itself, and so on. Even if the oxygen requirements of a tarantula are very low, which allows them to live in narrow tunnels in the ground, they won't last too long in wet stagnant conditions.

Edit (because I can't get my thoughts out all at once)...

Consider that housing a fossorial tarantula would require the same elements of taking care of a potted plant. A potted plant needs good ventilation and a soil with a balance of moisture retention, drainage, and aeration. Potted plants also use a container with a big hole in the bottom to allow excess water to drain away into a tray after watering.

Now consider if building a tarantula enclosure and caring for a tarantula in a similar way to a potted plant would solve a lot of problems talked about on this site. To do so, you would drill a big hole in the bottom of a plastic box, glue a screen on it, and put the enclosure in a big baking pan to collect excess water from watering. You would need a potting soil formulated for plants, but without the fertilizer, and use a watering can to water the soil. You would also need a lot of ventilation in the top of the enclosure for the water vapor to escape. Water the soil more often for tropical rainforest species and water less often for tarantulas that come from xeric regions. Putting it all together you basically would have built an enclosure that provides for adequate ventilation and humidity without worrying about mold and bacterial growth, just like a plant. Now who wants to try it out? LOL

Thanks for making a reference to my post about stress by the way. It is nice to know someone is reading my gibberish.

 

[l4nsky]

Consider that housing a fossorial tarantula would require the same elements of taking care of a potted plant. A potted plant needs good ventilation and a soil with a balance of moisture retention, drainage, and aeration. Potted plants also use a container with a big hole in the bottom to allow excess water to drain away into a tray after watering.

Now consider if building a tarantula enclosure and caring for a tarantula in a similar way to a potted plant would solve a lot of problems talked about on this site. To do so, you would drill a big hole in the bottom of a plastic box, glue a screen on it, and put the enclosure in a big baking pan to collect excess water from watering. You would need a potting soil formulated for plants, but without the fertilizer, and use a watering can to water the soil. You would also need a lot of ventilation in the top of the enclosure for the water vapor to escape. Water the soil more often for tropical rainforest species and water less often for tarantulas that come from xeric regions. Putting it all together you basically would have built an enclosure that provides for adequate ventilation and humidity without worrying about mold and bacterial growth, just like a plant. Now who wants to try it out? LOL

Pretty sure you just described a false bottom/drainage layer lol.