gourami with an owie

[LimpyFins]

my male gourami has what appears to be an abrasion on his mouth. i'll post a couple of pictures, but he was being a bit reclusive when i took them, so they're not all that clear. last night he was fine, and his behavior this afternoon is back to normal. when i fed him this morning, i noticed the spot on the left side of his mouth. there appears to be a loose bit of skin. that (in combination with it's sudden appearance) is what leads me to believe it's a wound and not a fungus. that, obviously, is my guess. any thought or suggestions?

20 gallon tank
pH neutral
0.5 ammonia
tank in nitrite stage of cycle
2 gouramis
4 tetras
rainbow shark

 

[val]

I'd think he probably got in a fight with the other gourami or maybe the shark. You're going to have to keep a watchful eye on that wound so that it doesn't get infected.

Valerie