I have a tank approximately 4 months established and I’d like to add som CuC. I thought hermit crabs would add some eye appealing life/movement so went to the LFS to pick some up. The owner ended up taking me out of it (weird right?!). He said he wished he never got hermit crabs for his personal tanks because they always get so big and eventually threaten the fish in the tank. Does anyone have experience with hermit crabs that stay small and won’t eat my fish a couple years down the road? My tank is 65 gallon total, 55 gallon display. Looking for recommendations!