What am I doing wrong?

[Guest]

Please help me!

For his tenth birthday, I gave my son, who is very interested in hermit crabs, an entire set-up and four crabs. I read and read everything I could find on the internet about hermit crabs, spent quite a lot of money, and put a ton of time into setting it up so they would be happy, but I still am having problems. I got a 20-gallon glass aquarium and mixed up substrate using one block of eco-fiber soaked in a gallon of salt water made with instant ocean with a 50-pound bag of Quikrete all-purpose sand. I mixed it all together into a consistency that would hold a sand castle. I later got crushed oyster shell and mixed it into just the top couple of inches. I think I followed all the substrate directions well.

My biggest problem has been achieving the right climate. I attached a small zoo-med uth to one side of the tank and I slanted the substrate so that there was less substrate over the uth (about 4-5") and more on the "cooler" side of the tank (about 7-8"). To be honest, the small Zoo-med seemed very small for a 20-gallon tank, but it was the recommended size. I also bought a Zoo Med African Mopani wood tree for them to climb and set up a moss pit with fish net up to it. Gave them two little hidey huts and both waters, and food dish. I also got a dual-sided light housing and put a Reptisun 10.0 UVB light in one side which we keep on whenever the sun is out, and a Exo Terra 50W night heat lamp on the other side, which we keep on all the time. Despite the uth and the heat light, I've been having a really difficult time getting the heat in the tank up over the low 70's. We live in CT and it is very cold and dry here at this time of year. We keep our house at 70 during the day. At night, when I turn the heat in the house down, the tank temp has been going down, too, and it may even be dropping a little under 70. I borrowed a seed flat warmer from a gardener friend and basically strapped it to the back of the tank, and so now with the undertank heater, the seed flat heater, and the warming light all going strong for days without end I have got the temp up to about 76 degrees. Now that the temp is up, though, it's getting a lot harder to keep the humidity up. And even that temp seems like it's too low! Should I get a different light? Should I get a second light and switch the Reptisun for a second heat lamp at night? Should I build a clab-gloo just to wrap the aquarium in at night? I don't want to bake the little guys. I got our 4 crabbies from a PetSmart and a Petco, so I assume they are PP's and want to be at about 80 degrees.

Meanwhile all 4 of our crabs, who we brought home almost a week ago, are doing a good impression of being dead. None of them seem to have eaten a single thing, although I've put two kind of hermit crab food and a variety of human foods in the tank, including peanut butter. I also think it's possible none of them have visited either water dish (although at one point I placed the big guy in the salt water to "show" it to him). I have read the message boards, and I understand this is relatively normal, but I still have concerns.

1. One dug down pretty early on and we've seen hide nor hair of him since. But he dug down in the corner over the uth at the back where I now have the seed warmer. That's definitely the warmest area in the whole tank (about 82-83 degrees). Could I be baking him?

2. About the same time, the littlest guy dug himself down under the tree. I thought maybe he was molting, but a couple of nights later it looked like his tunnel, which had caved in a little, was cleared out and he might have come out at night. Then last night I saw him out of the tunnel near its mouth. I thought, thank goodness, maybe at least one of them is done destressing, and I filled a tray with some fresh food and put it into the tank. I did this nowhere near him, at the other end of the tank, and I swear I was being very calm and quiet, but this scared him and he went right back into the tunnel and hasn't been seen since.

2. The biggest guy (about a 1" opening) was pretty active at first, even after the others had all shut down, but after a couple days it seemed like he succumbed and he dug himself into a hiding place under the tree and hasn't come out that I can tell.

3. The second to largest crab is in the front right (or coldest area) of the tank and I'll say "nestled" into the sand because he's not really buried, but he did dig down into the sand a little. He seems too exposed to be molting but he's been there for days and hasn't moved.

Before they all disappeared, when they were first exploring their crabitat, a couple of them seemed to get stuck in the fishing net and no one was able to climb it, so I took it out. Frustrating, because lots of interesting crabitats on the web had fishing net which is why I ordered it. I've decided to replace it with cholla branches which just arrived and I'm going to try to set them up so they can climb them up to the moss pit. The tree looked like an awesome climbing structure, too, but none of them have climbed it at all. All they've done is hide under or behind it. I don't get it. I read all these things on the message boards about crabs climbing, and playing, and cleaning out every drop of food in their food dish before springing back up to the moss pit. That is definitely not the experience we're having here.

Can anyone help? I'd just like one thing in there that looked alive! It's hard to get my son excited about doing hermit crab "chores" like feeding and cleaning water dishes when those things don't seem to have been used for the entire time we've had the crabs! He is doing a lot of misting, though. We're supposed to mist with the de-chlorinated fresh water, not the salt water, right? Very grateful for anyone who can help!

[Careyenz]

First question, and I may have missed this, but what are you using as a lid on the tank to hold the heat in? Your crabs are very new, so they may be destressing at this time. Unfortunately, survival rate can be pretty low for these little guys. The one who dug down is probably destressing or molting. I'm not sure what a seed warmer looks like, but you want to ignore the guidelines on the utH for size, and get the biggest one that you can fit on the side of your tank. Attach it above the substrate line and let the substrate just lie flat. Your crabs will never let it stay nicely slanted anyway.
You might want to look into foods from thehermitcrabpatch.com if you are using commercial foods. My crew has barely met a food there they didn't like.

I'll wait for a reply regarding your lid and dig further into the trouble your having. Good luck!

[Teedeums]

Maybe try and use a red 60 watt heat lamp, that is what I am using for my 16 gallon and the temp has been a lot better then it was when I had an UTH. You can find great deals on stuff like this on places like Amazon or eBay. Hope this helped!

[gotta-crab-em-all]

When I had a 20g, I needed two medium UTHs on at all times, with a UVB light on during the day and a weak infared heat light on at night. Nothing less would keep it at a proper temperature, even after I insulated the tank.

[KellyCrabbieLove]

Ok. I had a huge problem with this. I have a 125 gal tank. Buy one of these. The biggest one you can fit on the back of your tank. http://www.reptilebasics.com/ultratherm-heat-pads then go to the hardware store and pick up a package of styrofoam sheeting. I got a 6 pack for like 7 bucks. I put a layer of it over the ultratherm and gorilla taped it on really good. It worked wonders. To top it off i bought custom glass lids from http://www.dullesglassandmirror.com/gla ... e-tops.asp since then my heat is always between 79 and 82 and my humidity is perfect. Before both I had serious problems with both.

If you get your glass from them make sure you have a 2 -3 inch corner clipped on the lid for ventilation. I have that and then a screen lid over it so noone manages to work their way out of that opening.