I'm unsure of how compatible White Clouds are. Looking at my profile sets out my tanks as they currently are. I originally had 3 Black skirt tetras in the 10gal and 34gal with 5 White Clouds each. That apparently was a mistake because they started disappearing out of both tanks...ok not disappearing, but rather appearing inside my Black skirts mouths
. Anyway, I moved all the Black Skirts into the 34gal, and all the remaining (6 if I remember right) white clouds into the 10gal. Seemed ok. Then a few days later I added 4 Harlequin Rasbora's to the 10gal. I've never seen them fight directly, but as it stands today, I've got 3 white clouds left, and 3 Harlequin's, one of which has basically no fins or tail left at this point. So I can only assume that the whiteclouds in some form being quite active are either nipping or agitating the other fish, and then getting their asses kicked. It's too bad really, their nice looking little fish.