Personally I wouldnt get a Red Fin Wolf for a 125g. Some are active some are not. Depends on the fish. They typically max out at 8in. If you want a Wolf, go for a Gold Wolf (very active and get 15-18in). Or go for a Common Wolf (Less active until night 18-24in). Both are SUPER AGGRESSIVE and have some of the MEANEST JAWS AND TEETH in the fish world. Of course for the most part going w/ these species will probably put you with a single specimen tank, b/c they will eat other tankmates or if they are to large, just out right kill them. Good luck on what you decide...
