I would have to disagree with this. I really hate how pet stores keep 20-30 DG's (dwarf gouramis) in a single tank. This leads people to think that they enjoy the company of eachother. In reality, these are juvie DGs that do fine with each other, but once they get a little more mature, they can get pretty agressive with thier own species. I made this mistake when i first got into the hobby. I bought 4 DG's and put them into a 29 gallon (rookie mistake). These guys did nothing but kick the poopie out of eachother all day, staking out thier corners of the tank. I had to do some creative rearanging and move every DG to his own tank where they were happy as a pig in poopie. I currently have 2 DGs in a planted 125 gallon. They are great fish, and do well with all the other inhabitants (danios, cories, barbs, etc), but these two guys will manage to find eachother and have a little tustle before one backs down. Morale of this long drawn out rambling adventure is please dont add any more gouramis into your 6 gallon. One is just fine, and he will be happy with just about any different small, somewhat calm fish you decide to add with him. Good luck! And remember to keep up on your water changes until you get your cycle complete!!!