HCA: Hermit Crab Association

Hi guys! I was becoming very overcrowded for a while and felt so horrible and like I was failing as a crab mommy. But I knew there was now her near by that I could trust to properly care, or maybe there was, I just really didn't want to let go.
So I decided to build a bigger crabitat so that they could all thrive and live in a colony with enough space! (And now I have 4 ISO tanks!) They were up all last night climbing on shells and making lots of noise. I loved it.
Here are some pictures! I built this whole thing from scratch and I am really proud of it and I feel accomplished. I would love any feedback, what I can make better, what I did well, etc. Also, I have two heating lamps but I am highly doubting that will do the real trick, I keep hearing about some heating mat a lot of you use, should I try that? Link please? Thank you!
Here it is!
Here is Rosie climbing around on the netting.
Sebastian guarding his little pyramid that he can barely fit his big shell into the doorway of!
My little lonely guy, Claws. My only other E is in ISO because he had trouble molting. Claws just wants a friend of his own kind.
And then big Sebastian again, he doesn't like sharing.

I'm kinda confused, is there a lid?

I am still building the screen because we couldn't find one big enough so we have to make it ourselves. But I am managing to keep good conditions. c:

Got it
Also how deep is your sub, it looks a little low.

The sub varies, the back and right side are the deepest. Shallowest is about 5" and deepest is probably 8"-9". I thought they'd like options. cx

Looking good so far! You may want to deepen your sub all the way around to 8-9" - I know you have E's, and they like to have a lot of sand to dig in

What are the dimensions? It looks pretty good-sized!

Oh, and the UTH a lot of us use are Ultratherm - http://www.reptilebasics.com/ultratherm-heat-pads

How are you keeping heat and humidity in as well as preventing escapes? Don't underestimate their climbing abilities.

I also agree on deepening the substrate all the way across.

Megmaholm, I will definitely try to add some. Might be difficult because I just put them in and probably have borrowers and all of that. But I can still try to add some.
CallaLily, I have a few heating lamps and a heated blanket if needed. Also, humidity surprisingly isn't a problem currently, but I was thinking a blanket or cardboard if needed? (Any better suggestions?) And trying to get the UTH pad. (:
And yes, I know those crazy little guys can get around. But yes, surprisingly heat and humidity is going great! But any suggestions are ALWAYS appreciated.

Oh, and Megmaholm, it is about 5'6" by 2'6" I will look again to make sure for you, cause I want to know the exact too.

Wow, that's one awesome size - after some googling! I would love you know how you made it! BTW, does it include bracing?
For lids, I suggest using some cling wrap or at least some tinfoil to retain some humidity until you can think of a better alternative. (eg: tin foil around the heat lamps, cling wraps everywhere else)

That is a nice footprint! How tall is it? I'd love to see more pics once you finish the lid. In the meantime, closely monitor heat and humidity and see about finding a quick temporary lid of some sort to prevent escapes.

What is it set on/in? Can you post a full pic too?

ausieJJDude, we are going to brace a bit and I can tell you how I made it later because I am sadly busy for most of today.
CallaLily, I was aiming for about two feet but about a foot and a half I believe sadly. And I am keeping a close eye for sure. I am sorry, but what do you mean by a full pic, from the top showing the whole inside? o:

I think she meant a picture taken further back, to show what it's sitting on.

Asheka, ahhh, okay. We built and reinforced a table type thing built into the wall.

Yes, that's exactly what I meant. Thank you.