Injured Cichlid

[kawk5000]

Got a cichlid with a small "injury" on his tail, just before the fin.
He is an African Electric Yellow Lab.
The only guy in the tank (10g). I think he may have rubbed against a rock too hard or something.
What should I do about it?

Also, I don't do many water changes, I keep tap water in a gallon jug set aside for topping off when the water gets low. Is that a bad thing?
Been doing it since I started the tank.

He is the only one in the tank because he stresses out anything i put in there. He did have a tank mate (E.Y.L) that bullied him relentlessly... he died after an actual water change years ago. Since then he won't tolerate any tankmates.

Any suggestions appreciated.

[excuzzzeme]

Change water 30% weekly along with vacuuming the gravel. Failure to do water changes will allow dangerous build up of ammonia, nitrite, and nitrate. All these can be lethal to a fish if allowed to go unchecked.

ammonia in concentrations of .50 is lethal.
Nitrate in excess of 80 is lethal

Invest in a water testing kit and learn to use it. Read this article about cycling a tank. Your tank has already cycled but it explains water chemistry well.

http://www.aquariacentral.com/forums/showpost.php?p=661245&postcount=1

If your fish has an injury, failure to keep clean, healthy water will allow for infection resulting in death or serious complications warranting euthanasia.

[Rbishop]

Welcome to AC! Hope your fish gets well soon!