The tanks are 125 gallon, 120 gallon, and the 55 gallon. 125 has the 2 p.bass, and a couple of sunfish. 120 has the o, a convict, and some other cichlid i forgot the name but the con and her have breed a couple of times. And the 55 has tetras, mollies, guppies in it. As far as filtation 125= 200 gallon rated wet/dry with a 900 mag pump, the 120 two magnum 350's and emperor 400, and the 55 has one magnum 350 on it. I know a lot of people dont like magnum's but I love them tried different canisters, but just like magnums!