One of my 75's is open right now so recently I wanted to keep some goldfish in the tank rather than cichlids for a little change up. The tanks all set and ready to go as its already cycled and the temp is room temperature and all that. So, I know both regular "standard goldfish" and comet goldfish both really get too big for my size aquarium since they can both exceed a foot in length. So im assuming it would be best to stay away from those. I'm also under the impression that Shubunkins get too large for my tank size as well. What about fantail goldfish or black moors? I was thinking maybe 1 regular orange fantail, 1 calico fantail, 1 black moor, and 1 of somethin else. Would 4 fancy goldfish species be too much or is that alright for my tank size? I have two Marineland Emperor 400 power filters & i do weekly 50% water changes on all my tanks every wednesday if that helps answer any questions. Thanks everyone let me know what you think