HCA: Hermit Crab Association

I'm in the (taking way too long) process of setting up a crabitat. Being late spring here, it's pretty warm now... Definitely not warm enough for the crabs, but I am concerned about a UTH heating the tank too much. I guess I could always get a dimmer, but before I do: how much does your UTH usually heat your tank? Are lights a better choice?

It depends on the temperature of the room! A lot of members, including myself have had to insulate our UTHs using some sort of foam or other material. I have a heat lamp too, but they tend to dry out substrate if not kept an eye on, so most people shy away from that option.

And just to check, you don't have your UTH on the bottom of your tank right?

I really do like UTHs better then lights, and I have both. They are so much more fuss free, and the dimmer will do the trick if it does get too warm. Personally, I just unplug my UTH when it gets too hot in the summer. Haven't quite got to that point yet.

thanks! And yes, I know not to actually put it under the tank. thanks again!

A related question, can a UTH be used by itself (understanding insulating it may be necessary)?

Here's why I ask. I have a red reptile bulb on a 10 gallon tank, in a closed room with a closed AC vent. It works so well that I think it's heating the whole room up. However, I am thinking this isn't going to work as well in the living room on a 55. Plus, I have a couple of monkey cats, and I'm not sure I can find a place to put it that they couldn't mess with it. And heating up my entire living room just isn't high on my list of things do to heading into a Texas summer. So, I'm wondering if one of those long Ultratherm ones, 35 or 47 inches long, might get the job done.

It's usually an either/or thing. Either you go with lights, or you use a UTH. One or the other should get you enough heat, but some people who keep their homes cooler sometimes need that extra boost, especially if it's something other than an Ultratherm or if the pad is too small. My 15 gallon that I use the UTH on stays a toasty 72-87 gradient all winter long, and it's in a spot in the house that regularly sees below 60 degrees. There's a Fluker brand pad on that one, but those don't come large enough for a 55 gallon.

Trick is to go with one that is as big as the back of the tank. If you don't need a ton of heat, go with one that will sit above the substrate line. Ultratherms are the most recommended brand out there.

Okay, looks like what I need then is the 11" by 47" inch one. Thanks!

Insulating the UTH made a big difference for mine. The heater raised the temp from 68F to about 75F. Adding some insulation raised it up to about 82F.

Ultratherms can be insulated, right? Styrofoam and then aluminum foil? Do you have to use the kind they put on houses, or will any kind do?

Yes, ultratherm's can be insulated. I would do aluminum foil, then styrofoam. Doesn't have to be insulation board. I've seen people use cardboard instead. Mine is insulated with one of those things you put in car windshields when parked to keep it cooler - shiny side facing into the tank to reflect the heat in instead of out.

Oh, cool, there's options i hadn't even thought of. Could you use an emergency blanket instead of aluminum foil? Though, aren't those technically some kind of plastic? That may not be a good idea.

An emergency blanket would be ok. I don't think any UTH would get hot enough for it to be an issue. Mine was reading 97.5F in the middle without insulation. Once it was insulated it, the temp gun gives me a reading of 111F in the middle on the glass (it was also warmer in the house).

My Flukers have hit 140 if I try to insulate. Normal running temp for them is 110.

so i finally attached my ultratherm, 47x11 on yesterday. i just slapped it on the back and used some packing tape to hold it on, it's not 100% flat by any means, and maybe like the bottom 2 inches are covered by a piece of cardboard i had covering the substrate. The temperature would peak out at 82 and bottom out at about 77 before I put it on. It's been on now for less than 24 hours. and right now at 10am (i put it on at 5pm yesterday), it's at 90, i'll know tonight what the low is at night since it didn't record it as it hasn't been a full 24 hours and I didn't see what it was at. But I'm thinking it may even get higher based off of what it's done so far. I'm thinking it'll make my tank go to 85-92 average, from 77-82 like it was before. We'll see, but so far so good. I'd like to see a little more activity out of them, and I think this temp change will be perfect.