I have 4 glofish and yes I know their little mutants but I did not realize this until I did some research on them and found that their color was unnatural. But I have them now, so as long as their little gills are still pumping I'll take care of them.. Now they are supposedly a schooling fish (zebra danio) and you are suppose to keep 6 or more.. I have 4 (2 red 2 yellow) and the biggest of the 4 (a red guy) pretty much dominates the top of the tank chasing any of his kin away. Could this be because I only have 4? If i was to get 2 more would this aggression taper off? Any thoughts, thanks.
I had no idea what GloFish were (by name) until I googled them and the first thing that came up had a trademark thing next to the name and I realized what they were. Ok, back on subject, yes, normally with schooling fish, if you get more, they tend not to be so aggressive, I've also heard that you can get a big aggressive fish to scare them into schooling and playing nice, but I would go with buying more.
Every once in a while you'll get a bully. I also think a few more would help. If you have plenty of plants for them to skip in and out of they should be ok. Your school should be big enough that everyone should have a playmate.
If you want to spend less money (and get 5 or 6 more), you should be able to get regular zebra danios to school with them - they are usually less than a dollar each compared to the more than 5 dollars per Glo.