I keep forgetting to post about this, but after another test again tonight I figured I would. I have a mixed tank of goldfish and a few axolotls that have some of the most fast acting virulent ich I've ever seen.

Around 6 months ago, I took in a few goldfish from someone that had what we determined to be carp pox. They were healthy and active, however quite ugly, so I decided to not euthanize them. Eventually they cleared up and were removed from quarantine into a tank with a few axolotls as from my reading the carp pox shouldn't pass to them.

A few weeks later, I had a lone oranda that had come in with some feeder comets and after it had been quarantined I moved it in with the rest of them. Within about two hours the oranda was covered. Fins, tail body, nearly the entire fish with ich. So I moved it out back into it's old tank alone and started treating it. In about 18 hours it had died, and the orange goldfish was near white. After that I decided to try one of the comets thinking it must have just been some sort of fluke that the oranda broke out like that. The comet took closer to 4 hours, but was also completely covered in ich and also died around the 18 hour mark. Everyone else was just fine, so I decided to just leave the tank alone, outside of adding a little pond salt.

Fast forward to today, I dropped in a new unrelated comet. Same thing again, near instant vicious ich. I know ich can linger, but I was stumped on what it was living on since there's nothing else showing any symptoms.

That is very odd, I don't know what to say because that is so odd and especially sense no one else has anything.

I've never heard of ich moving that fast. Or any other fish disease for that matter. I did have a fish die from some disease in about 24 to 36hrs. I'm not 100% sure what it was but I think it was velvet.

Hmm, haven't been on ina coupla days.

So let me get this straight. Do you think the oranda and the comet caught the ich from the tank with the existing goldfish and axlotls? Or do you think they caught it from the Qt tank? Regardless, I've never seen ich act that fast. I've heard people talk of it before, but have always considered it hearsay or exaggeration. Dawg may be on the right track, except I assume you can tell ich from velvet.

Gotta do some thinkin' on this one. There has to be a logical explanation.

WYite

Yes, there's something in the goldfish/axolotl tank, and no it's isn't velvet.

Both the oranda and comet I used were quarantined in a different tub. All of the fish from the oranda batch became snacks, but I didn't notice anything on them and currently none of the other feeders are showing any signs of anything either.

I've been mulling around a few theories in my head, but haven't had a chance to do any real research.

One of the things I was thinking is that ich is a protozoa, and that it may be a different species than the common Ichthyophthirius multifiliis. That however leaves me stuck as to why the carp pox infected fish are immune to it. I suppose I could put yet another feeder in and once it gets sick to set up a few slides, but while I could maybe id ich under glass, I'm not so sure I could id a different species. I'd be all yup, it's a protozoa all right.

Well, did some homework. Tilapia (Xu et al, 2008), channel cats (Wang and Dickerson, 2001), and carp (Cross, 1993) can develop antibodies (surface immobilization antigens) to ich which prevent further infection. I'm sure these are not the only species that can develop immunity to ich infection, just ones that have been studied and recorded, so that may give an explanation of why the formerly pox-plagued goldies aren't catching it. And if fish can develop immunity to one ciliate parasite, they probably can develop immunity to others.

Have several ideas to get ya goin' and I'll look more later this evening when I get up (just got off my last graveyard shift). First, I'm wondering if it's truly ich, as in Ichthyophthirius multifilis, or if you could have another ciliate with a similar, albeit quicker, life cycle. Second, wonderin' if it's possible that there are so many dormant cysts in the tank, especially if the goldies in that tank developed an immunity, that the addition of a host without immunity causes an instant attack of a huge number of parasites, overwhelming the host fish. Third, wonder if the parasites in that tank may not have developed a bit of an immunity to medications. Possibly a combination of two of these, or all, or maybe none and something different all together.

WYite