HCA: Hermit Crab Association

Another question....I have a 20 gallon reptile tank. For heating I have an 5"X7" and a 4"X6" under tank heaters which the person at the pet shop assured me would be more than adequate. They are not. I added a 11"x17" under tank heater on the back of the tank and covered it with a homemade insulator to force the heat forward. At night I cover the tank with a folded towel to prevent any heat/humidity loss, leaving a small strip exposed for air circulation. Depending on the house temp, the tank temp fluctuates about 10 degrees from low 70's to low 80's. I know since the lid only covers 3/4 the top of the tank, I get some heat loss there, but again, I prefer that there is some air circulations. In the smaller tank I always kept the lid open a crack. As others have mentioned my crabs seem happiest in the low 80's. For winter I am thinking of adding a heat lamp over the exposed portion of the screen to help boost the in-tank temps. Any suggestions?

Heat lamps are only recommended for tanks 30gallon and larger due to the restrictions/limitations present with smaller tanks.For a twenty gallon you need a heat pad rated for a sixty gallon to get the right temp boost as these pads are only meant to boost the tank temp up seven to ten degrees from room temp.Do you have the other two uth pads mounted on the bottom of the tank?

Yeah, make sure all UTH are mounted on the side - they won't heat the tank well from underneath and are very dangerous to digging/molting crabs!I think my crabs would rather have a warmer tank than air circulation, but I've never had mold issues so haven't really had to worry about that. My lid is usually only cracked open a bit and have not had issues.

Thanks for the speedy replies. Yes, the two smaller UTHs are mounted on the bottom of the tank. In my 10 gallon they were on either side. And though the thermostat said the temp was good, I found that they constantly stayed huddled against them. I went to the pet store and was told--no, no put them on the bottom which I did. Then the boys completely shut down. So I did a bit of reading found the bigger one, fashioned my homemade insulator, and we were good to go. Still I worry about the fluctuations--especially for winter. If a heat lamp isn't an option, I guess I will go to another UTH for the side of the tank and cover up the top except a crack. Thanks!

Yeah bottom mounting is not an option for hermitcrab enclosures as these pads were never designed to be used with hermitcrabs and so do not work at all when mounted per the manufacturers instructions.Your actually putting burrowed, molting or tunneling crabs at risk for overheating since uth work by heating the glass first then radiating the heat upwards and outwards through the substrate the depth and dampness required by your hermitcrabs acts as an insulator actually trapping the heat against the bottom pane forcing the temps to rise well over 100 degrees which will bake a hermitcrab relatively quickly as hermitcrabs don't feel heat the way we do they will stay put and cook themselves.Think of it like this in the wild a hermitcrab burrows to get away from the heat of the day because the further down you dig the cooler it gets so it would counterintuitive to put a heat source where one doesn't occur naturally.I highly recommend unplugging the two pads mounted on the bottom as they are doing more harm than good at this point.99% of the people who work at or own a pet store have no idea what they are talking about when it comes to hermitcrabs so we always advise coming here first to get your questions answered as you'll rarely get the right info elsewhere.

OMG, seriously? You are so right, these people don't know a darn thing. I gave up on the pet stores after the sales person told me my two small heaters were more than adequate for my 20 gal tank--but before I found this forum. So frustrated. Fortunately tomorrow is cleaning day. I will take the heaters off the bottom and pray that their adhesiveness will be adequate for sticking them to the sides of the tank--otherwise hello duct tape until I can get to the city to buy replacements. For foster crabs they are darned expensive creatures! I am so glad they have been banned from being sold in Canada. The idea that they are disposable pets, sold by uninformed morons infuriates me. Thanks again for the info.

Your more than welcome for the info. If you have any more questions please don't hesitate to ask as that is what the community is here for.I've gotten to the point when associates at Pet-smart see me walking in they try to ignore me because I intimidate and infuriate them with how much I know and I've never been pushy with offering info to them they just don't like being upstaged by anyone who isn't wearing the store uniform.lolI basically have to help myself when I go in to shop and any new employees that don't know me quickly learn that they don't know as much as they thought they did when they attempt to help me.I don't mean to be a know-it-all but I don't like it when I hear someone else being/acting dumb when I know they could do better.I guess it's not the generally being smarter than everyone else around me that rubs them the wrong way it's the way I point it out constantly that does it. The only way I get intelligent conversations is to come on here because this community is full of smart like-minded people such as yourself I guess thats why I'm on so regularly.lol

I did the deep clean today. The boys are both back in the tank, happy as hermit crabs can be. The change of scenery to their small tank did them good as they ate all the popcorn I put in while they were waiting--then chowed down on the chicken and roasted beet I put in their clean tank for supper, and are now having fun eating the carrot top tree we put in (a tip I found on this forum). Their appetites haven't been this good in a while.I baked their rocks and driftwood while I was cleaning the tank. When I finished putting in the new substrate I put the warm rocks in to help bring the coir up to temp--which worked well. We took the UTH off and put one on each side of the tank. Fortunately the one little critter which started this whole process must not have had any friends as I didn't see any while scooping out the substrate. Anyway, everything is right in their crabby world. Thanks again!