HCA: Hermit Crab Association

My hermit crab seems like he wants to change shells but doesn’t like any ive been getting, his shell opening now is about 1.5 inches what size shell should I get and does anyone have recommendations of where to get them?

Thank you so much!

I am a new hermit crab owner, I have been researching them for months and finally came upon a pair that were being poorly cared for. So I got the correct tank, a 15 gallon glass tank. They have plenty of substrate which they love to bury in(probably because they were neglected) and eat regularly. Th...