I have 3 hermit crabs. I have two little ones and a jumbo. For some reason, the jumbo has started viciously attacking the smaller ones. He has never attacked them before, but has always been aggressive. He literally ripped off a few of the other hermit crabs legs. Basically, I have him in his own tank now by himself. I know they are supposed to be community animals, but I am afraid he will kill them! They were together in a 10 gallon tank. Is this just a faze or should I keep him by himself?