Other then goldfish it started for me when my dad bought a big tank off trademe it came with some very neglected black widow tetras and golden barbs when my dad went to pick up the tank the water was solid black! We did not use this tank for a while and the tetras and barbs went in with two goldfish in a smaller tank non heated tank and actually suvived for over a year active and healthy then we set up the bigger tank we got plecs cichlids clown loachs gourami and tetras that went one for a while then we down sized completely as dad no longer wanted the tank but we could find a home for the big Pleco and the jack dempey so we had to keep it raning the pleco got far to big for the tank so we donated him to the winter gardens where he now lives in a big glass house pond dad gave the tank and jack dempey to a friend at this point I only had my gold fish fatso left she has about 8 I took her down to wellington on my lab on the plane she went well for a quite a few mouths until we had to put her down because of swim bladder problems I had gotten some other goldfish to keep her company then but about a year later when I was on holiday the tank had a melt down and killed them all I had a completely pink one now I just have my little tropical tank with Corys tetras loaches and some little sucker cats I am in the process of getting them in to a much bigger tank and in case your wondering well I was in auckland these latest hoilydays my dawf puffer died he never so much as snipped a single fin