Tank had marine velvet, now what?

[lutz123]

Background...The nano with my 2 clowns recently had what I'm almost positive was marine velvet. It could have been ich, but honestly had a strictly velvety appearance. It started quickly with my possum wrasse. At one point a couple of months ago, he had one tiny spot and it was gone the next day. About a month ago it came down with a more "velvety" look and stopped eating. I euthanized it when it became apparent there was going to be no recovery. In the same time period (24 hrs) the two clowns developed it but continued eating very well. I opted to wait and see. They took about 10 days to fully pull through but are fine now. I do remember back around Labor Day one of the clowns had a cloudy look to the tail, but it disappeared quickly. I have added corals, etc since then so who knows the original source.

 

So the question is, what now? I am not adding any more fish, but now that they are healthy should I pull them out and run fishless for a month? Will leaving it as be just perpetuate the cycle?

[gmerek2]

From what I have read it seems like its your call and there is no right answer. You can keep em fat and happy to boost immune system so the immune system keeps it in check. Then hope they dont get stressed enough for it to lower immune system and come back or you could try treatments. Looks like copper treating is wishy washy, hyposalinity wont work and formalin dips 37% are risky with killing/stressing the fish. My clown had it and I ended up killing it with rapid build up of ammonia from the fish not eating in quarantine. So my advice would be just keep formalin 37% in hand, hope it never comes back and if it comes back strong treat right away then quarantine the reccomended amount of time to kill what is left over in tank.

[lutz123]

So what about adding fish in the future? If I don't go fishless but leave the tank as is for awhile, is that enough?

[YHSublime]

If your fish are currently eating and happy, from my understanding is it's not velvet. Velvet acts quick, and can wipe out a tank.

If you end up catching and QT'ing your fish, you will want to let your tank run fallow for 8 weeks. Any additional fish added should be QT'd for 4 weeks, disease or blemish free. That means if they have anything, that's 4 weeks of waiting after the last sign of "sickness."
 

But since you say your not planning on adding anything else to the tank, there's probably no point in stressing your current fish out. If they are healthy and eating, I would feed properly and be done with it. Follow my journey with QT from the beginning, you will find lots of answers in there!

[sachabballi reef]

i agree with isaac I highly doubt that was velvet.it would wipe them all out immediately typically, its a fast and cruel disease.

are the fish breathing ok now or are they struggling at all? can you get a picture?

[lutz123]

Yeah, I thought that too, but it just didn't look like ick. Either way, the two clowns look perfectly healthy and have remained that way for a week or so. So how do I proceed knowing that I will never be positive what it was? Would it be worth it to put them in a bare hospital tank (and treat "proactively"), while letting the tank run fishless? Or just let it be? I may want to add another little fish at some point and am not sure when it would be relatively safe, or when I could transfer corals out of there.

[gmerek2]

You could treat prophylactically with copper it's safer, takes a really long time. The choice is yours! If it were me "if it ain't broke don't fix it" my advice is keep copper on hand so if they get sick again, pull all fish and QT immediately. If they turn nose to food any time throw live brine or live black worms at em.

[davelin315]

Velvet can strike very quickly, but it doesn't always strike right away.  You can be lulled into not doing anything and then have it explode on you... when my tank was wiped out the fish exhibited and then showed signs of improvement and then bam, all dead within a couple of days.

 

Velvet, like other strictly fish diseases, will die without a host after a set amount of time.  I'm unsure of exactly what the life cycle is, but my tank has been fallow for a long time...

[Wrench]

I had it in my system a few years back and not all fish were affected. I lost about 30% of my fish before deciding to take action. I set up a 200 gallon hospital/treatment tank in the basement and left the main system fallow for 12 weeks. Not easy to do with 20 fish but it worked. During the 12 weeks I treated with copper, Maracyn 1 & 2 and Prazi Pro. Since then all new additions are QT'd. With a nano, I'd imagine you can do it fairly easily with a 10 or 15 gallon tank. Then you'll never have to worry about it again. 

[astroboy]

I'm not sure if this has any bearing or not, but it's an interesting story that I think raises some interesting points, so please bear with me. 

 

When I moved this summer I took the rock out of my 29 gallon, leaving three clowns and a six line wrasse and corals in the tank. Had 2-3" of sand (mud) which I left undisturbed. Everything did fine during the two months I set up my 90 gallon. 

 

So, I moved corals and fish (and a big wad of chaeto) to the 90, where they did very well. A few weeks later I bought a really nice looking powder blue tang from a very reputable source, and put it and a few corals from another good source in the 29 (using it as a QT), which still had the sand in it. I had left the protein skimmer running and aside from some hair algae things seemed to be OK. 

 

The corals did fine but in 24-36 hours the PBT had a bumpy skin with very small white spots, smaller than any ich white spots I've ever seen. After three days the spots and bumps went away and the fish looked and acted like a champ, but a week later they returned and the PBT died within 12 hours. The store I bought it from said they'd had the PBT for at least three weeks and it had been 100% healthy and I'm sure that was the absolute truth. 

 

I figured that the PBT had picked up some disease that had been latent in the 29 for two years, although 24-36 hours didn't seem like a very long time for anything (ich, velvet, brooklynella) to appear, nor did the really small white spots, followed by a mucus like slime right at the end, really look like those diseases.  Bob Fenner does mention some parasite often seen in tangs that lurks in tanks which can hang around for years, but which usually isn't lethal or even really serious, but does show up within a day or so. I can't recall what it's called. I thought that might be it. Still, you'd think a 2 year old disease-free display tank would be a decent QT.....

 

Anyway, I figured the PBT had been infected from something latent in the 29 and was now in the 90, so I decided to let the 90 lie fallow for a couple of months. Of course, it's possible the PBT picked up something in 24 hours from the corals I'd bought, but that's a really short time and I've talked to some knowledgeable LSH owners who have told me that it's rather unusual for fish diseases to be found in exclusively coral tanks. Of course, there might be other LFS owners who would disagree with this, and neither of the owners I talked to claimed this was gospel, so please don't read anything deep into that statement!!!!  All I'm saying is that I figured my PBT was infected by my QT ex-display tank and not by the corals I bought (so quickly). 

 

So, I managed to catch the clowns and put them back into the 29 which had been their home two weeks before, and in 24 hours they had swollen cloudy eyes and were covered with slime, and all died overnight. Rather sad, since I'd had them for two years. I hope they didn't suffer too much. 

 

On the other hand, the six line wrasse I couldn't catch so I had to leave it in the 90. After 10 days I devised a fish trap and caught it and put it into a sterile tank. It looked (and still looks, two weeks later) as healthy as a horse, even though I had moved the corals from the 29 QT into the 90 during the week the PBT had been looking good. 

 

So, it would seem that 1) there was something in the 29 that killed the PBT and clowns, even though it had been a good display tank for two years, and 2) no diseases were carried by the corals I bought (or else the wrasse would have been infected). It's possible the PBT was a carrier and got sick from the stress of a new tank, but then the 'germs' would have been on the corals I transferred to the 90 when it looked OK. This all sounds like Koch's Postulates on pathology, which is the only thing I recall from high school biology. Possibly the wrasse has some immunity, but when you add it all up I don't think a disease was the problem. 

 

Steve and Vince from Quantum Reefs told me some time ago that PBTs exposed to low pH (say, 7,8-9, I think ) will exhibit bumps with very small white spot, which I had completeIy forgotten, otherwise, perhaps I would have avoided this whole sad scenario. I suppose that's a result of some sort of osmotic skin trauma, but that's just an ignorant guess. It sure sounds like that's what my PBT had, anyway.

 

You would think that clowns would be more resistant to just about everything than a PBT, but something in the 29 killed them. The only thing I can think of is that some sort of pathogen or toxin really ramped up with the low pH (or vice versa) and killed both the clowns and PBT. What it could have been, I have no idea. It seems strange that a tank where clowns had done well for two years could have turned toxic somehow in 2-3 weeks, (but didn't hurt the corals, apparently) but that appears to have been the case. 

 

Possibly, the rather deep (and old) sand bed had a sulfur dioxide burp, but it seems like that would have killed the corals.

 

It's all a bit of a mystery. Unfortunately, during the move I lost my pH meter so I don't know what the pH in the QT or display tanks was. All I can say is that the corals looked pretty good, so my guess is that it couldn't have been much under 7.6-8, say. 

 

So, does anyone have any experiences or insights into what might have happened? As I said, it would seem that conventional illnesses, such as ich, velvet, or brooklynella, were at work. Is it possible that a tank from which rock, fish, corals and chaeto have been removed would be so unstabilzed in some way that it would be lethal to a hardy species like clowns?

 

My point, after this long winded discussion, is that the problem that lutz123 saw with his clowns sounds alot like what killed mine. I think my experiences have (probably) ruled out ich/velvet/brooklynella infection, but it seems possible that bad pH (??), which might well occur in a small tank and which might have occurred in my 29, in the absence of fish, corals/chaeto, might give rise to pathogens or toxins which are really bad news for fish, but not necessarily for corals.