So I used to have the boys sharing a split 2.5 and they were mighty happy with it, so I figured when I moved them into their own 2.5 tanks they'd be ecstatic. WRONG. Damn mopey fish have spent the past three days drifting about with clamped fins and a shade grey. I thought they were sick, turns out they were sad because they couldn't see each other anymore. I slid the tanks up so one side abuts and their happy as pigs in mud. my fish are insane.