I put a quartet of Melanotaenia boesmani "German Red" (from Marcel's stock) in the 30 long with bristlenoses a couple of weeks ago. Last night, two of the females were sparring for a long time, at least 45 minutes. Their coloration was incredible! I had never seen the females color up so much. If only they'd stay this color all the time! Short crappy video. Much prettier in person.