Two new crabs, terrible conditions

[Specks]

Heya, so today I got two new pps from an urban pet store I found. I didn't intend to buy any crabs, but i saw a beautiful glossy pastel pink beauty walking around and I couldn't say no. I was about to pick her up and buy her when I though I may as well just get two. I chose the sickest one there. The conditions were really terrible, it was about 15 crabs in a 4 gallon "tank", a faded, yellowing plastic bin with no lid or humidity. The store had mixed their freshwater with their food in order to save space (and create mold and ammonia buildup), and they were sitting in at most half an inch of calcium sand. There were also no unoccupied shells. I chose a medium sized boy with the world's tiniest shell. A crab his size required about a 1 inch opening on the shell, his shell had about a 1/2 inch opening. He was curled up into his shell as far as he could go, yet his eyes and a bit of his abdomen were poking out. His eyes were cloudy and it looked like he hadn't been submerged for weeks. I picked him up and gave him a whiff to see if he was dead. I didn't smell anything, so he was alive. I asked the store worker about him and he said "oh you don't want that one, hes probably dead" and then proceeded to snatch him out of my hands, drop him in the water bowl and splash him with murky water until his claw opened up. The poor thing was so stressed out. I bought him and brought the two home. During the car ride, he actually got up and started walking around the tupperware. I ran inside, and set up and isolation tank for them at the speed of light. I gave them a chicken bone, some honey and some egg shell along with about 7 new good sized shells, set up a heat lamp and misted the whole tank down. He's quite active, but still very frail. What can I do to increase their chances of survival?

[soilentgringa]

All you can do is provide them with good conditions, nutritious food, and the correct waters. Sounds like you are doing everything you can, just leave them alone and wait.

[Specks]

Thanks, the scruffy one just changed shells so things are looking bright.