Black spot disease outbreak?
Good Evening WetWebMedia crew members.
<Yawnnnnn! Good morrow to you>
I have recently traded a blue line trigger for a yellow tang (+ a Kole) since the trigger grew to 8 inches long and started becoming highly aggressive. My system is 157 gallons with mostly soft corals. Problem is that when I was at the LFS, under their normal fluorescent lights, I was unable to see 3 little black dots on the yellow tang that I immediately spotted when I placed him in the main tank (under 450 VHO watts). The LFS guy said not to fresh water dip the fish because it would stress it out, if not kill it.
<... which is more stressful? To you, the fish? To have your system infested with Turbellarians? Or a simple dip/bath? Bad call.>
I also do not favor this method too much because I lost another yellow tang to an 8 min fresh water dip 3 years ago - as soon as I placed him back in the tank his buoyancy got messed up and sank to the bottom, only to die a few minutes later.
<Was the freshwater (presumably) dip water pH adjusted? Aerated?>
So, I properly acclimated yellow tang Number 2 and introduced him into my setup, since I had no quarantine tank. Since day 1 (1 month in my tank), the yellow tang has had 2 outbreaks with the black dots. He doesn't scratch, eats well (has devoured all my Caulerpa algae and does not appear to be skittish.) I have attempted several times to catch
him, however, it is impossible to lure him with food.. he constantly hides (well, I'd do the same thing If I were him). My question is, is this disease deadly since he eats well, and all behavior seems to be normal?
<Not "very" deadly... just persistent, semi-debilitating>
Will he ever recover by himself if not treated / left in the tank?
<Mmm, not likely... the "tank has the disease" now... a balance can be struck with biological cleaners (Lysmata Shrimp, Gobiosoma gobies...), but Paravortex will live in a tang-free environment for months at times... w/o hosts>
I hate to tear off the tank completely to catch him ( I have 25 corals + 120 lbs of LR. I have read this Paravortex flatworm or whatever, does not affect other fish (currently I have 2 other tangs with the yellow one) but it's hard to get rid of. 
<Yes, you are correct>
If the fish does not deteriorate due to the flatworm, do I still need to remove him from the tank?
<Mmm, no>
Any advice on what to do would greatly be appreciated. WWM site is simply invaluable.
Thanks for your help,
Dimitris
<I do wish we could go back in time... I could convince you to at least quarantine this Yellow Tang.... if not dip it... I would go the cleaner route here. Bob Fenner>

Re: Black spot disease outbreak?
Hello Bob,
<Dimitri>
Thanks for writing back. How's the weather in San Diego?
<Bunk, overcast... been a very rainy winter...>
I live in Largo, FL.. similar weather but very humid most of the time 
<Very nice>
I did purchase 3 peppermint shrimp to fight this...
<Mmm, not Peppermints... Please read here: http://www.wetwebmedia.com/clnrfaqs.htm>
...so hopefully they'll do their thing. Yes, I agree with the fresh water dip but I had a bad start with the other yellow
tang, so I was naturally afraid (I also listened to the LFS guy ). I just wish the supplier(s) in HI would actually dip the fish before they ship them over to the LFSs (could have saved me a lot of headaches).
Dimitris
<Yowzah! You're so right... this is a campaign issue I've been waging for going on thirty years in the trade... Really makes not sense not to... to bump off your customers... their livestock... over such a simple procedure... Bob Fenner> 

Paravortex "Black Spot Disease"  11/11/05
WWM Crew,
Recently my Yellow tang showed signs of Black Spot Disease (little black dots covering its entire body) after a few days they were gone, and then a few days later they were back.  I hope my diagnosis was correct.  I followed Mr. Fenner advice from the book The Conscientious Marine Aquarist (great book) and gave the Tang a fresh water bath (pH adjusted & aerated) for 10 min and it did very well and knocked off all the black spots.
<Good>
After the bath I put it in a 20gal by itself.  Two weeks later there are no signs of Black Spots.  First question, how long should I keep the tang in the 20gal before putting it back into the main tank?
<About another two weeks>
Second question, how long will the Paravortex survive without a host?
<A few weeks typically>
Third, are my fish in the display tank (72gal bow) at risk for contracting the disease?
Currently in the tank I have 1 Bicolor Angel 6" (doing very well contrary to reputation), 2 True Perculas (pair), 1 Lawn Mower Blenny, 2 Blue/Green Chromis, and 1 Yellow Tail Damsel.
<Mmm, there is a possibility these fishes might act as "reservoir hosts"... Ideally, all would be processed per your Tang, isolated, the infested system allowed to run fallow for a month...>
I practice good maintenance; all tanks (3) get a 10% water change twice a week and parameters are stable and were they should be.  Please lend me some advice, my Bicolor Angel misses the Tang and likewise for the Tang. They are good buddies.
Thanks in advance,
Bryan
<Heeee! Soon to be reunited. A thought... adding a purposeful cleaner... perhaps a Lysmata Shrimp or a Gobiosoma goby... might add interest to your system as well as utility here. Bob Fenner>

Re: Paravortex "Black Spot Disease"  11/12/2005
Mr. Fenner,
Thanks for the information. I guess I should have mentioned that I do have one Scarlet Skunk Cleaner Shrimp in the tank as well as a few soft corals, one Bubble Tip Anemone (opposite end of tank from corals), Black/Red star, and other hermits and snails. 
<Ah, yes, thank you>
I sure hope that the others are not acting as a reservoir host, they show no signs. The cleaner shrimp has been cleaning the Bicolor Angel regularly. He also cleans the Chromis too. I think I will leave the Tang out for another 3-4 weeks just to make sure.
Thanks again.
Bryan
<If this doesn't work out (this time) it is not that big of a deal to "re-do"... Paravortex is not "very debilitating". Cheers, Bob Fenner>