Yellow tang - please help me diagnose

[guitarfish]

I have a small yellow tang and a blue YT damsel in my 20g QT tank. I've had them for 30 days, and they have been at 1.008-1.009 for 21 days.

The tang is very twitchy and "darty", has been since I got her. She tries to scratch on the rocks. Every fish I've ever gotten at the LFS where I got these two has had ich, so I wasn't surprised by the behavior early on. The damsel behaves completely normal, incidentally.

I have never seen any ich spots on the tang. I have seen them on other yellow tangs and other fish, so I know what I'm looking for. If the tang had ich when I got it - 30 days ago - those parasites should have detached at some point and the itchy behavior should have ceased at some point.

This behavior aside, she eats a 1" square piece of nori every day, and is also eating frozen Formula 2.

A week ago I took the tang out and did a fresh water dip (I did this thinking flukes may be the culprit). After matching the FW to the same temp & pH, I did a 2 minute dip. I wanted to do at least 3min, but the tang didn't like it, went on her side immediately. In any case, I never saw any change in behavior.

I don't know what to do at this point. The tang is obviously being bothered by something, but what? The little blue damsel has never exhibited scratching behavior, noe shown any spots, by the way.

Opinions please!

 

[arizona tech]

i would leave them in hypo for 2 more weeks, that scratching might be just a "itch" but if your lfs is having ick problems then keep them in hypo 2 more weeks

 

[BTTRFLYGRL]

Four weeks in Hypo should do the trick..Are you doing daily water changes? Poor water quality can make fish itch. Be sure to check PH as it drops during hypo...are you using a refractometer? He could very well have flukes. Hypo does not kill this parasite, only slows down its reproduction. Could also be a bacterial infection of sorts. I would continue to watch him, finish up the hypo.....once you start to raise the SG , if he has flukes, they will show up . Formalin dips are better for flukes..Not as stressful IMO.

http://www.petsforum.com/personal/trevor-jones/formalinbaths.html

You can do the dips while he's going through hypo, make sure the dip water is the same salinity

 

[guitarfish]

Thanks for the suggestions. Yes, I'm using a refractometer to test the SG. This is a well established QT, the water quality is excellent. I think I have some formalin...I'll give it a shot.

Thanks again.

 

[ATJ]

Dave,

I agree with your assessment that it is not "Ich". I don't believe it is Amyloodinium or Brooklynella, either, as the fish would either be dead or have fully recovered. I don't know what to suggest it might be, but a formalin bath would not be such a bad idea.

Run the full course of hyposalinity and then assess the fish's behaviour for a couple of weeks after that before adding it to the display tank.

It is possible it is just a peculiar fish.

 

[guitarfish]

Thanks Andrew! Always great to have a visit from the doctor.

 

[guitarfish]

Last night I decided to dose my QT tank with Formalin 3. It seems pretty safe to use. It states that it can be dosed every 24 hrs if needed, provided 25% water changes are done.

The fish are OK this morning, once the lights are on, it'll be interesting to see if there's any changes in the tang.