Sick apisto :(

[boyohboy]

I have a trio of apisto in a big tank (not other fish yet). Just the last day or so, the male is looking kinda sick.

His mouth (lips) seems to have a little fungus-like stuffs on it, and/or maybe the lips are just a lil swollen?!
And also start to notice his stomach seems to be bigger than usual. Haven't noticed any worms of any sort yet (touch wood) tho.

How should I treat him?

The 2 females in the same tank are looking fine and eating normally so far.

Thanks

EDIT: oh after seeing the sickness appearing, I just did a ~40% waterchange last nite.... if that helps, I hope

 

[fishgeek]

water parameters would be first check, apisto's are more sensitive to nitrogenous waste products
oxygenation maybe reduced with certain by products and larger fish are more susceptible to lower oygen saturations

motuh fungus is actually a bacterial codition and is usually secondary to some other problem- again water quality is a possibilty

is the fish still eating or do you think the belly is large for other reasons
any red streaking on paler parts of the fish's body

which species so we can advise on best water aswell

andrew