Zebrafish getting beaten up?

etanico

I have a 5 gallon tank with 4 Zebra Danios. Yes, I just became aware that this is actually considered "overstocked" and am working on getting a larger tank.

But recently one of my fish has had a couple problems. First, a fairly large cut appeared on his side. As if he scratched himself on something. But that has since healed.

Just today I noticed that something is seriously wrong with his spine (I'm assuming). He is a little crooked. He seems to be able to swim fine, but I mean...his spine is bent. I don't know if this is the result of another Danio's aggression towards him (I wasn't aware they were aggressive...). Is there anything I can do for him?

ANY advice is GREATLY appreciated. :(

Varkolak

I would probably say genetic defect, danios in general are notorious for being imbred so badly they end up with bent spines and short lifespans. If you say your overstocked with 4 minnows I wont argue with you but I wouldnt be worried about it - to be sure check your ammonia levels and do a decent sized water change, if its not genetic its most likely a water issue so a water change is a good precaution.