I have a 220 gallon community tank with 3 adult male flowerhorns and six adult female flowerhorns with no problems.The only FH that gave me any trouble was my kamfa, when I tried to introduce him to the community tank he attacked everyone, so he has his own tank now. As far as the other FH's losing color because of a dominate male thats not true mine are all very colorful and the fact they are together seems to even make them more vibrant !!! I think the dragon strains tend to be more accepting of tank mates but space has alot to do with it to.