HCA: Hermit Crab Association

I just have a quick question please. If it is key to keep humidity in then the holes I drill to hang their uvb light from on the inside of the lid should be enough ventilation for them shouldn’t it? Thanks in advance.

I would say you’d need to try it first. I have a UVB bulb exposed in my tank there for air can flow through the light fixture and out of the tank because I have remove the glass that was under the bulb to allow the UV to get into the tank because glass filters UV. Even though that allows some airflow I still have to provide a small opening in the corners of my lid. If I don’t do that my humidity stays too high and starts creating other problems within the tank. Too much condensation causing the substrate to oversaturate. But you also need to be aware that your light could melt the plastic. You might need to put some aluminum foil in between the lid and the light. Get some aluminum duct tape or just tape on some foil. Hope I’ve helped a little bit. I think your idea will work and I think you actually need to end up drilling more holes but you never really know until you actually do it.

Links, thank you so much! What you say makes perfect sense. I will do the aluminum foil and drill more holes.

I have an aquarium with a mesh lid completely covered in tinfoil and bubblewrap. At first I thought it would be bad for the hermits since no air can get in and out, but someone mentioned that the air circulation happens every day when I change their water. I would assume that it works the same way for a tote, so maybe you don't have to go too crazy with the air holes?

You know, that’s true. Maybe I could just do that. I would be taking the lid off everyday so they would definitely get that exchange of air. Does plastic give off any kind of fumes that are harmful to the crabs that you know of? @avamin2005

Don’t drill more holes if you don’t have to. Set it up and see how it goes. You can always drill more holes later is what I meant. Just like my lid, I crack it open a little more if my humidity is 99%. But the way mine is set up my humidity goes up when the light goes off just like in nature. Humidity always goes up at night because the air temperature falls closer to the dew point. When humidity and temperature are the same humidity is 100%. Theoretically it should be raining when temp falls to match dew point but not always the case. Anyway my temp slowly falls a few degrees when my light goes off which is why I get that effect. Also the exposed light bulbs zap humidity as well when it’s on. Usually, my humidity is near 90%+ just before my lights turn on. Then it slowly drops to 80% by the end of the day just before my lights go off. The more I “crack” my lid the lower my humidity will be.
As far as fumes from plastic. I’d be wary of any plastic fumes from hot plastic. Others have used totes so I’m not sure how they heated them or provided light. I think someone had a clearish tote that got some natural day light.

@links. Thank you so much for the reply. That makes sense. I will set it up with my uvb on the inside of the lid and keep an eye on everything. Can’t wait to do this at the end of the summer