Reason I say 200 gallons, is becasue these guys get pretty big, and I was thinking of their quality of life. I would suggest dividers, because they may or may not get along. Or they may get along until that one fatful day, or night, and you go check, and disaster! They are animals/cichlids, and are unpredictable. I dont think you want to take a chance and lose your very nice fish. That would suck. I have all 3 of those cichlids now, and they are of my top 5 favorite cichlids. I would use 200 gallos +, so if they are divided, they are not crammed into a tiny square, at least withh 200 gallons, they have a bit of swimming room, to be themselves, and also because of the waste and metabolites these guys produce, especially as they grow. You want to give them lots of water for health issues too. Sure you can keep them and try your chances in a community setting in a 75 gallon, but thats more of a prison sentence or UFC match up. I keep my 10" male beani and 6" female beani together in a 110 gallon. Trust me, I cant keep anything else in there, even if I took the female out, the male will try and kill any other fish. The Istlanum, are very mean to each other, and the ones I had, went head to head with a big Jack Dempsey, all the time. I had to remove the JD, as he stood his ground well, and beat the algae out of 1 Istlanum male. My grammodes. I have to keep him by himself, as he is a psycopath, and attacks every fish, even my male Mota. The Grammy is 5" and the Mota is 8". Maybe I have pyscho fish, and others dont?? But I would not take a chance if I were you, but that is just me.
eyespot;3186344; said:My old grammode got to be 6"+ and did well in a 265 gallon community cichlid tank. The only other guapote was an 8" female managuense. My roommate had a 5" islantum from Rapps that wasn't terribly vicious in a 55 gallon (I forget his tankmates). The only one that I have no experience with is the Beani, who I've read at 8-10" is going to be the nastiest and biggest of the bunch (ordering one from Rapps?). It's trial and error with crafty cichlids, but if it's going to work I don't think think you need a 200 gallon aquarium with that bunch, probably just a 75 with lots of driftwood and rockwork territory. It's more about luck than volume., IMHO.