I'm getting ready to buy a 125 gallon tank this week but still undecided on the fish. I don't want breeding pairs and nothing over 6" if possible. How many and what kinds should I get? I thought about convicts, firemouths, blue acara. Will these be alright together and do these fish grow shorter than 6"? What else could I put in with them....remember no pairs. I want the tank to be full if you know what I mean. Thanks!