Well, I just noticed that one of the other males in the display tank has developed a weird protrusion on top of his back. I managed to get some more photos. It seems to have appeared out of nowhere & looks like a tiny grain of rice atttached to his skin (similar to what the female had on her tail). Again, he has no other symptoms and is chasing the females around trying to breed lol. I honestly don't know what it is... the spots & patches seem to pop up very suddenly & then disappear without any other obvious symptoms (other than scratching). I just did a WC yesterday & now all of a sudden this spot has popped up & I saw my biggest female trying to scratch herself & having a bit of a frantic/jumpy swimming pattern (no skin changes though). All the other fish are calmly cruising around the tank & she's glass surfing in one corner - she's been doing this on and off since I got her, though.
The quarantined male perked up and stopped shimmying after I removed the meds and did a big water change (and added a few floating plants to make him more comfortable). Which is a bit counterintuitive... He's now marinating in some salt
, we'll se if that helps.
I'm now torn between some kind of ectoparasite, tetrahymena (since it's a livebearer) or epistylis (I hope not)... but I've heard conflicting things about it. Some people say it's deadly and progresses quickly, others say it isn't. So I'm not entirely sure what to do. The fish aren't showing any signs of a bacterial infection. But if it is epi or tetrahymena, is the treatment basically the same as for ich (methylene blue & malachite green) - assuming the are no additional infections on top of it?
Note: this is a new tank (~2 months old), but last I checked the parameters were all fine... unless there is some kind of bacterial pathogen in the water, but then how do I get rid of it without nuking the biofilter and every living thing in the tank? Would a few big water changes be enough? Or maybe a UV sterilizer (the kind you mount on the internal filter outlet) - would that also potentially eliminate any free-swimming parasites?
