My tigers are lately being extremely vicious to each other. My biggest one has barely any font find left and his rear tail the bottom half has been nipped. I have 1 fish that's tearing thru the tank like a bat outta and harassing everyone. His colors seem to be paling and I dont know what to do. I have 18 in there, 2 golden dojo loaches and 3 nerite snails. Should I put my big in a quarantine type tank til his fins grow back? Will they grow back??? Please any ideas or advice would be appreciated!