Black Skirt Tetra Question

[andyb325]

I have two black skirt tetras that i've had for about a month, and last nite and this morning i noticed that their fins became really dark/black and then within minutes it was almost completely gray. Is that normal? Also on thier very back fin, they both have a few white spots. I know it sounds like ich, but for as long as i can remember they have been there, and i have not noticed any more on them, or on any of my other fish. My friend thought it kind of looked like small spots of white mold maybe? If anyone give me a little info i'd really appreciate it. Thanks

 

[Holly9937]

I'm not sure about the white spots, try and do a search on cotton fungus. As for the changing color, mine have done that too and it kind of freaked me out. I think when it happened though, my heater had went crazy and the temp. changed more than it should have, so it might be a stress thing, make sure your water conditions are all ok!

 

[jnr102030]

this is normal well i um not to sure lol i think it can be stress tht cause it now cum to think of it
cos i hav 2 black widow and one always chaes the other one
black chases widow but blackk has a black fin and widow has an almost transparent fin