HCA: Hermit Crab Association

Is it possible to seal up small holes in shells and have them be wearable for the crabs? I understand they need to keep shell water and holes in the shell would be bad for that. I have a couple shells that are great aside from small holes...I was thinking of plugging them with hot glue but have seen others on here warn against using that. What about natural grout or something? Anyone tried plugging holes?

Aquarium silicone would be a safer material, you would need a skilled hand to keep it smooth on the inside.

What if I used a tiny mesh patch made of plastic then aquarium silicon over it? Ive seen people use that method when drywalling (obviously with different materials ). I might try it seeing as the shells are pretty much useless with holes anyway.

Wax paper, the mesh would create a texture I don't think the crabs would like. I've never tried fixing shells I have a massive collection so shells with holes get sent to the unwanted bucket. If you can cover the hole lightly on the outside you may not even need to use anything on the inside to keep it smooth. How big is the hole? If it's small enough I would just try to cover from the outside with out filling in the hole to much

Marine epoxy putty, the kind that reef keepers use to attach frags. Waterproof, rock solid, and non-toxic.