Single white cyst, spread to second fish

[PCG]

Hello all,

I'm sorry that my first post here is a desperate plea for help, but here goes.

I have a 75g tank, 0 ammonia, 0 nitrite, >20ppm nitrate. pH is 7.3-ish. Water changes once every week and a half, about 25-30%.

I have a geophagus that developed a small cyst (I'd say maybe "pin head" size...if not then very slightly larger) at the base, near the back of his dorsal fin. The white part of the cyst is sticking out...not a lot, but when he turns to the side, you can see it protruding. You can also see it from the other side of the fish, like it's deep inside. It's not ick, as I've dealt with that a few times in the past. Today, I noticed a similar cyst on my green barb, but this one is in the middle of his body.

I caught the geo in a net yesterday and rubbed the white part of the cyst with a pair of tweezers. When I put him back in the tank, the white part appeared gone, and some red damage was visible. Today, the white part is back.

I've been reading all sorts of forums over the past two days, and while I've seen some people post problems that sounded similar, a lot of the solutions do not look like what the geo and barb have, like columnaris, and lymphocystis.

Sorry if the info is a little vague. Has anyone else come across something like this?

[young_cichlid]

ive never had this problem but try some antifungal medications. it kinda sounds like ich

[PCG]

Hmm...I might go so far as to say I'm 100% certain it's not ick. I've battled that before. This cyst looks...angrier (some red around the one on the geo), and it's only one on each fish. I have anti-fungal stuff as well as a bunch of antibiotics. I think I'm going to move both fish into a hospital tank and hope no other fish get it. I'm just wondering if I should treat the hospital tank with the anti-fungal stuff or one of the antibiotics...or maybe it's a type of parasite.

[young_cichlid]

hmmmm a parasite is more likly than ich if its just 2. good luck!

[droopy1]

I have had something similar on 2 of my betta fish, just behind the front fin one developed a large white lump that had a fleshy frayed look, and impeided on the use of her fin, I treated the tank for rot and ulcers. (MYXAZIN) My 2nd female betta also started with a white lump in the same place?? As I had already treated the tank I waited. The 2nd betta cleared up quickly, and the 1st is now clear about 4 weeks in! I looked up what not to do etc, and found a site that said leave well alone and wait and see. Neither fish were ill looking or off their food, and both are fine now. Mine is a community tanks, barbs/neons etc...no others had it.
Not sure if that helps.