I have a 55 gallon freshwater tank filled mostly with 3 large gourami fish, several tetras, guppies and platy's. I also have some cardinal tetras. We recently bought a white freshwater lobster as the pet store said they were generally shy, stuck to themselves and bottom feeders. I have noticed him going after my smaller fish and today he clawed one of the gourami's in the head. I still have 2 weeks to return him and I am seriously considering it. Does anyone know what the long term effect of the lobster in the tank is? Will he get more aggressive and wipe out my tank? I thought he would be a neat addition but I am seriously rethinking my decision. Any suggestions would be welcome! Thanks!