I have a 150g with 1 male festae, 1 loisellei, 1 jag and 3 severums. The only aggressive behavior comes from the severums. Would a Pike be an optional tankmate? More specificaly one of the lents that Rapps has? How big and aggressive would I expect one to be? Can they be kept in the same water chemistry? Thanks in advance, btw, all fish are between 5-6" I believe the fish Rapps has is between 7-9