Male sailfin molly

I am looking for some help please. My orange male sailfin molly's mouth has gone white and isn't eating. The day before yesterday he was being 'bullied' by the other male sailfin molly causing him to become exhausted but he was still being harrassed. I put the 'bully' in a breeding net for a few hours and this did the trick, when he came out he left the other male alone. Today the orange male has got a white mouth and can't eat. It looks as though I am going to lose him and he is my favourite. Could it be stress or could there be something wrong with my water.

My water parameters are Nitrite - 0 Ammonia - 0 Nitrate - 20 General hardness - 7
I did a 20% water change today and added some melafix. I also added 1 tbs of aquarium salt with the water change.

Other fish in the one year old 50 gal tank are:

4 female mollies
2 golden gourami
2 female dwarf gourami
6 silver tipped tetra
5 harlequin rosbora
2 black widow tetra
4 leopard cory
3 ghost shrimps
1 pleco
2 snails

Please help

Hi again,

I have taken a couple of photos (not very good ones) to give you an idea of the problem.

Noone answered yet. Hmm.. Looks to me like mouth fungus. That's the only thing I know of that causes the mouth to go white.

I see that alot with the larger mollies. I would have to agree with zappylady, its probably some kind of fungus. I would relocate him though, it's contageous.

It could be Columnaris (Flexibacter) a rather nasty highly contageous bacterial disease!! - Unfortunately every time one of my fish has had it, it turned out to be fatal