I aquired a boseman and a dwarf rainbow when I bought my last tank (fish came with the tank). I already had two blue rams and I had no problems. The rainbows stayed towards the middle and top and the rams pretty much stay at the bottom. Supposedly rainbows are a schooling fish and like company. I got rid of the Boeseman because he was to big (5") and I just did not care for it (Traded in at the LFS for store credit). The lone dwarf rainbow schools with my harlequin rasboras.