FAQ How can I cool down my tank?

Morganthe asked:

My sisters and I received crabs over the summer. They were seperated for a while because of budget constraints (we had three small plastic fish tanks, but nothing big enough for multiple crabs) but have since been moved into one large tank back in my bedroom, a glass ten gallon with a glass fishtank lid. Their living conditions are better now than they were, but theres still one concern. My parents HATE the things, and when my apartment goes through I’ll be taking them with me, but for now they are trapped in the south-east corner room of the house. I live in the desert and this room is always warm. Ever yheater I could kept tempertures steady at a level above the ambient room temperature, but my room temp is already too high (85F). I’m currently hanging dechlorinated ice cubes from a thin bag with a fan near the tank. I spary the glass top of the cage to keep the humidity up. This works fine in the afternoons and on weekends when I can attend to the crabs hourly, but I need to find a way to regulate the temperature when I’m not around. I’m currently turning off the fan while I’m away, which increases the temperature, but prevents high evaporation rates. Does anyone know of anything that will lower the temperature in the tank? I’ve read everything I can get my hands on, but they all seem directed at people who have cold winters and pleasent summers.

Ladybug15057 answered:

Prior to getting our central air conditioning, our tanks would hit in the upper 80’s. Using a fan does help to circulate the air, but unfortunately dries the humidity in the tank which the hermies need to breath. What I had done, was I saved 16 oz. plastic Pepsi bottles. I filled them 2/3’s full of water and put them in the freezer. I used a Kool Aid cap (or other plastic lid) as a drip basin and pushed this in the substrate. I then put the frozen soda
bottle in the Kool Aid lid, with a couple of small sponges around the space between the Kool Aid lid and soda bottle so the little hermies didn’t get stuck and freeze to death. This made a cool place in the substrate if the hermies wanted/needed a place to cool off at. We did have a couple of hermies throughout the day that took advantage of the cool substrate in all our tanks. One thing I noticed about the frozen soda bottle, was that the outside of the bottle would be full of condensation, and at times I would have to empty the Kool Aid lid. I also noticed the humidity of the tank dropped, which meant that I had to use larger sponges to keep the humidity up.

PS. If you choose this method, start saving your soda bottles. The soda bottles would keep ice in it 4-6 hours on a ‘hot’ day. I would exchange these about 3-4 times a day, refreezing the ones I took out of the tank. Make sure to keep a close eye on the humidity level. The soda bottle will pull some of the humidity out of the tanks air so you may need to supply other water sources as well to keep the humidity level up. (you do have a lid for your tank right to help hold humidity within the tank?)