[Jacob]

I have one female nagyi that has black marks on her dorsal, and a few black marks on her upper body and one on her tail.
It looks like random melanistic blotches, black coloration with no texture. Most of it is on the dorsal, several blotches. The tail has two smaller blotches.
There are two males with her, I saw black splotches on the tail of one of them, it is showing breeding color and acting fairly normal, still has the splotches though. The other male is hidden in a cave and I can’t see him.
I don’t think the other separate tank which has one pair in it is infected, or hasn’t shown it on the fish yet.
Any treatment, other than water changes and cleaning out rotting material, to try?
If the fish stays the same with these markings on it, is it likely that it will still reproduce and if it does is there some health problem passed on to the offspring?
It’s probably a matter of time whether or not it improves on its own, gets worse, is contagious, etc.
This tank does have a snail problem, and has had live blackworms as food.
If the disease is black spot, snails are said to be part of the life cycle of the parasite.
If it is environmental, caused by rotting material in the tank, maybe it should then clear up with improved conditions.
Copper sulphate is mentioned as a treatment for black spot, but that would probably be dangerous wouldn’t it.
Maybe salt or flubendazole works, I’m using flubendazole soon anyway for hydra.