I've had this fish for about a year now. This stuff started appearing about 6 mths ago and has recently started getting much worse, as in spreading over more of his body. It used to be only near the base of his tail but now is on his head as well. It appears to be coming from between his scales.

It looks a bit like the kind of oily gunk that comes out of human pores.

It must irritate him as he often slaps his side against plants or the thermometer, although not constantly.

It is worse on one side of his body than the other, It's not white spot and is unaffected by either Wundertonic or Furan-2.

I have occasionally taken him out of the tank and successfully wiped the stuff off with Melafix and cotton wool. But it starts coming back after just a few days.

He has about 80 little fish mates and he is the only one that has this.

Has anyone else seen this before, or have any idea how I can treat this problem?

Not easy to tell from the picks but my guess would be whitespot and the fish is producing extra slime as a reaction to that.

I have a rainbow fish with what looks like that around its gills and occasionally the odd spot or three appears elsewhere on its body. Its been like it nearly all year. The spots move around the body and the number around the gills vary. The only fish affected by the spots and no other symptoms spotted. Its like teenage zits.

Not easy to tell from the picks but my guess would be whitespot and the fish is producing extra slime as a reaction to that.

Really? He's had it for about 6 months now and I did have a couple of platys get white spot a few weeks ago, and the Wondertonic did seem to get rid of it from the platys within a week. It was the same tank so that would have got rid of it from my little Gourami as well if it was the case. Regardless, if it is just too much slime, then that's not a bad thing is it? Just doesn't look nice.

Its like teenage zits.

:sml1: Yes it is a bit like the stuff that comes out when you squeeze a zit. I hope that's all it is. It is getting a bit worse though lately. He's getting old now and started to slow down a bit. Maybe I'll just wipe it off again. Not sure he enjoys that experience though. :dunno:

Thanks guys for the quick replies though.

Indeed think it's white spot (in a progressive stage). The parasite will damage the slimecoat and makes the fish vunerable for secundairy infections. White Spot-parasite only can be killed in the swimming-free stage of it's lifecycle (so you don't cure the spots at the fish). That's why you have to treat with most meds for about 5 days in a row or even longer.

Dwarfs are also prone to Iridovirus. Don't think yours have this disease, but maybe interesting to read.

http://www.aces.edu/dept/fisheries/educ ... uramis.pdf

Cheers Aad