Pondering Effectiveness of Cross Ventilation

[Bemottled]

Disclaimer: All of my Ts. True Spiders, and Ball Python have and always will have adequate cross ventilation. I have no desire to science-experiment them to death.

Hello!
I've got a (basic) question.
When I was building my ball pythons cage, I decided to put in lots of cross ventilation. This was along the same line of thought from my A. avic setup- cross ventilation, to allow ventilation but to keep some level of humidity in. (Since BPs need between 50-70%) So I added a ton of CV and kept a hydgrometer in with some wet paper towels to measure things over the course of 24hrs, mostly to see if I could stop adding holes, or if more were needed.
Despite me adding more holes, and widening more holes, I never got it to anything below 90% humidity. Sides dewed up, really awful if there was actually a living creature in it, essentially. This didn't go away until I added holes to the lid of the container as well.

So my question in all this, is what actually makes cross ventilation work? Why exactly is it necessary?
For example- I understand that A. avics live in treetops and that they get (horizontal)breezes and such. So I can understand effectiveness of CV paired with, say, an electric fan. But in still air, as most keepers have, how does it work?
It seemed very ineffective at ventilation when I was building it into the enclosure.
Just curious!

Thanks,
-Bemottled

 

[grimmjowls]

That's a really good question, actually.

Not one I have an answer to, but one I'll be happy to learn about if anyone does have an answer.

 

[Venom1080]

i never use just a cross ventilated cage. i always have some holes on top as well.
sorry, dont have much to really offer here, cold blood or poec will probably chime in soon though.

 

[Envoirment]

You also put holes in the top of the enclosure, not just the sides. I have 3 rings of holes on the side my Avicularia sling's enclsoure. One just above the substrate, one at the top and a ring with holes further apart in the middle. On top of this I have a ring of holes in the lid. I feel that airflow in your room is an important factor. My windows are usually open most of the day and they have small air vents that are always open, so my room has good airflow. So far my sling has been doing well (have kept it for over 6 weeks now).

 

[Oroborus]

Well I'm no expert by any stretch of imagination, but any sling losses l've suffered have been due to ventilation and humidity levels. Of course after it happens I realize I should seen the signs, but unfortunately that's part of the learning process. Anyway, humidity and ventilation and the correlation between the two are determined by a number of variables. Ambient air temperature affects the level of moisture it can carry; the type of substrate will affect how much moisture it will hold and how long, and seasonal humidity will affect evaporation, or lack thereof. The problem with high humidity and poor air movement is that it can result in fungal spores that can infect the tarantula's book lungs. This can particularly become an issue if one has poor custodial practices and bolusses are allowed to build up and decompose. Regardless of the level of ventilation holes provided, if the relative humidity where you live does not permit evaporation your custodial habits are that much more important. In my opinion the higher the humidity level maintained in an enclosure, the more room that is required for essential air exchange relative to ventilation. This largely why I dislike pill bottles and switch to small deli-cups as soom as possible. Sorry, I've prattled on and have no doubt forgotten certain variables. I guess in short, keep it clean, keep it ventilated and modify the amount and type of substrate as conditions demand. Cheers.

 

[AphonopelmaTX]

The point is to provide a well ventilated cage and to do so you don't need cross ventilation. Ventilation is one of those aspects of tarantula husbandry in which there isn't just one way to do something. For years when I kept Avicularia species, I housed them in those large Kritter Keeper style enclosures turned on end so the plastic screen lid is facing me. I didn't bother drilling holes in the top, back, and sides because the plastic lid provided enough ventilation. I housed large Poecilotheria species the same way. If you have a plastic box for instance and drill many holes in the top and sides to provide that cross ventilation, it will be no where near as well ventilated as a glass aquarium with a screen lid even though there wouldn't be any holes in the sides of that glass aquarium. Most of the trouble I've noticed comes into play when someone uses a small plastic container to house immature tarantulas. These types of containers don't have the surface area to drill or melt enough small holes in just one side so more has to be added on all sides. One then might assume that cross ventilation is the key to the husbandry of some species when in fact, it's just good ventilation in itself that provides an adequate environment for raising small spiders or spiders of any size really.

It's important to keep in mind what you need to accomplish with husbandry techniques instead of trying to figure out the details of just one way to accomplish it.

 

[EulersK]

Personally, trying to achieve cross-ventilation has been more of a hassle for me than it's worth. Even with more than adequate ventilation on the sides, I end up with mold 100% of the time if I have no ventilation on the top. Unfortunately, this means that I need to water my spiders far, far more often than if I didn't have ventilation on the top. I gave up on it awhile ago. If I can get an A. avicularia to grow in an enclosure with limited cross-ventilation, then it's clearly not that important.

 

[Bemottled]

Thank you everyone for your responses! Especially from the in-depth ones. After hearing CV stressed and preached all over backwards and sideways, I'm very happy to learn a little bit more about it. This question has been nagging at me forever and it's awesome to finally have answers to it.

 

[Abyss]

One could argue (i skimmed so this poitn may have been made) thats its not ventilation or cross centilation that one is actually trying to achieve but air flow/air movement.

I have done this (and do this) by venting the sides of course BUT i always add a few holes at the top but to me, the key is adding holes at the bottom as well.

The premiss:
Hot air rises so in theory, cool air will enter through the bottom holes naturally as the warmer air rises.
Imo, this naturally creates a slight flow of air through the enclosure.
ALL my arboreal enclosures are done this way to great success. For adults, i display my T's so all have those fancy nice acrylic enclosures that come with the 1.5" vents already in the sides. From there i simply drill about 6 (possibly more depending on enclosure size) holes in the top and the drill a good ammount of holes across the front just beliw the door.

I think the key is creating a natural air flow as just holes at top to me doesnt do much except let humidity escape. And holes only on the side wont do much of anything really unless your artifically moving the air with a fan (even a ceiling fan should move air enough).

Thats my theory anyway, hot air rises pulling cool air in an thus you get a naturally created air flow (one could further argue that no vent holes are needed on the top probably)

 

[Trenor]

I put a lot of holes on the sides and just a few on top to prevent condensation build up. I have found that if I put too many up top then the enclosure dries out really quick. For me, side ventilation is a bit more forgiving where as it doesn't seem hard for me to over do top ventilation. In the end, I agree the important thing is to have enough ventilation.

 

[Poec54]

Cross ventilation allows air movement throughout the cage, which helps control mites and mold. With fewer or no holes in the lid, a microclimate is created along with air exchange. Cross ventilation is part of a well-ventilated cage. Some members may live in climates where other strategies work. Ironically EulersK in the Mojave Desert has mold problems, but in wet, steamy Florida, I don't, where cross ventilation does work.

Top ventilation (without cross ventilation) compromises the micro climate, examples being screen tops and kritter keepers, both of which I wouldn't use. Open lids (or sides) can expose the spider to hot/cold drafts, sprays, fumes, etc.

 

[viper69]

When I was building my ball pythons cage, I decided to put in lots of cross ventilation. This was along the same line of thought from my A. avic setup- cross ventilation, to allow ventilation but to keep some level of humidity in. (Since BPs need between 50-70%) So I added a ton of CV and

Interesting you gave your BP cross-vent. I've raised BPs and never have done that, with no issues. You aren't doing anything wrong mind you, just different than me.

I've also never measured my BPs humidity, no issues.

Now Brazilian Rainbow Boas, and Amazon Basin Emerald Tree Boas are 2 snakes that immediately come to mind where humidity levels are important or health issues arise if kept too dry.

Also remember, while you perceive air to be still, it's a gas, and thus its molecules are constantly moving. Even a simple room can have air current eddies in it.

 

[Bemottled]

Interesting you gave your BP cross-vent. I've raised BPs and never have done that, with no issues. You aren't doing anything wrong mind you, just different than me.

I've also never measured my BPs humidity, no issues.

Now Brazilian Rainbow Boas, and Amazon Basin Emerald Tree Boas are 2 snakes that immediately come to mind where humidity levels are important or health issues arise if kept too dry.

Also remember, while you perceive air to be still, it's a gas, and thus its molecules are constantly moving. Even a simple room can have air current eddies in it.

I feel much more comfortable measuring my BPs temp and humidity, along with a lot of other things, just so I know potential causes if something goes wrong. Any incomplete sheds, stress-fasting, RIs, etc. My only proper care experience is in tarantulas, so I'm not experienced enough in herps to keep from making stupid mistakes Also you already know I'm a meticulous person, haha

I'd love to keep Rainbow boas and tree boas someday... baby steps though.

Good point on air molecules though. My physical science experience is minimal and far away (like freshman year of high school), I never thought of that.

 

[Bemottled]

Cross ventilation allows air movement throughout the cage, which helps control mites and mold. With fewer or no holes in the lid, a microclimate is created along with air exchange. Cross ventilation is part of a well-ventilated cage. Some members may live in climates where other strategies work. Ironically EulersK in the Mojave Desert has mold problems, but in wet, steamy Florida, I don't, where cross ventilation does work.

Top ventilation (without cross ventilation) compromises the micro climate, examples being screen tops and kritter keepers, both of which I wouldn't use. Open lids (or sides) can expose the spider to hot/cold drafts, sprays, fumes, etc.

Sounds like a lot of interesting nuances. Is there a reason that drier climates experience mold problems with CV, while wet climates do not? It seems.. yea, pretty ironic. And puzzling.

 

[viper69]

Any incomplete sheds

That never worries me, except if the eye caps don't come off, and for me at times one hasn't. Even though I don't worry too much, I remove it. There have been times where the BPs container was more humid a bit, and yet an incomplete shed occurred. And less humid, but complete shed occurred.

I've often wondered if the fluid that develops between a snake's new and old skin is not always the same amount and contributes to difficult shedding.

 

[Trenor]

That never worries me, except if the eye caps don't come off, and for me at times one hasn't. Even though I don't worry too much, I remove it. There have been times where the BPs container was more humid a bit, and yet an incomplete shed occurred. And less humid, but complete shed occurred.

I've often wondered if the fluid that develops between a snake's new and old skin is not always the same amount and contributes to difficult shedding.

I haven't raised too many snake but my ball python used to have a time during the sheds. Moisture was the problem as it was often to dry with the wire topped cage. I thought about changing the mesh out for plexiglass but never did. I added in a large water bowl that he could fix totally into and since I can tell when he is getting into shed mode because he'll be in it. No problems shedding since and I've had him for 9ish years.

I've often wondered if the fluid that develops between a snake's new and old skin is not always the same amount and contributes to difficult shedding.

Maybe if they are dehydrated due to lack of humidity they can't make as much fluid and that leads to harder sheds.

 

[viper69]

I haven't raised too many snake but my ball python used to have a time during the sheds. Moisture was the problem as it was often to dry with the wire topped cage. I thought about changing the mesh out for plexiglass but never did. I added in a large water bowl that he could fix totally into and since I can tell when he is getting into shed mode because he'll be in it. No problems shedding since and I've had him for 9ish years.



Maybe if they are dehydrated due to lack of humidity they can't make as much fluid and that leads to harder sheds.

My ball refuses to soak sadly. However he never refuses food thankfully!

Maybe relative humidity affects that, I honestly don't know. I don't know enough about that aspect of snake physiology. I doubt in my case because the humidity doesn't change that much indoors, but who knows.

 

[Bemottled]

My ball refuses to soak sadly. However he never refuses food thankfully!

Maybe relative humidity affects that, I honestly don't know. I don't know enough about that aspect of snake physiology. I doubt in my case because the humidity doesn't change that much indoors, but who knows.

If you humidity is around 70% when the snake goes into/is shedding, you should get full sheds every time. When I had my ball in an aquarium setup, I had to dump soaked sphagnum moss in and mist a lot, which was bad, so she's in a tub now. Humidity and temp sit perfect and I get full sheds every time
Ofc I'm sure as long as the eyecaps are coming off and you don't have stuck pieces larger than a couple inches, it's fine. There's always more than 1 way to keep a snake, haha.
I've seen some horrible stuck sheds before though Don't understand how people can leave their snakes like that. I love the healthy glow Chai gets when all her shed is off.

My indoor humidity changes constantly, gets super dry in the winter, less dry in the summer (also when I have to leave her tub cracked to let out excess humidity).

 

[viper69]

Don't understand how people can leave their snakes like that

Agreed, esp when I read people's snakes have 3 eyecap them!!

 

[cold blood]

Agreed, esp when I read people's snakes have 3 eyecap them!!

What? People just leave them on? C'mon, help a snake out