Powder Blue Tang - Lethargic, not Ich

[Satori]

When I got home from work today, my PBT was lethargic, with his belly just resting on the sand. I fed the tank, and he didn't move to eat.

I was able to reach in with my hand and lift him out. Now he's in the QT tank with water from the main tank after a water change. There are no visible signs of ich or external parasite.

He's almost 2 years old, I got him from a friend of mine 9 months ago. All other fish are doing great.

Water tests:

Alk: 9.6 (always steady with a ca reactor)
ammonia: 0
nitrites: 0
nitrates: 0

I feed nori, frozen mysis, frozen brine, bloodworms, cyclopeze, formula 1 cubes. (alternate feedings) every day.

I keep up on maintanance on the tank, crystal clear water and healthy inhabitants.

Can anyone give me any ideas?

Thank you in advance.

**edit - he was swimming around great when I left for work this morning**

 

[SWSaltwater]

If I had to guess he might have been in a fight, what are the other tank occupants? Sometimes PBT's go south fast, very sensitive fish. Wonder if the interceptor had anything to do with it.

 

[Satori]

Good point Rob, I forgot about the interceptor.

I treated for red bugs this weekend with interceptor. I haven't heard of any fish problems resulting from this treatment, but everything has to be considered.

Other fish:

Yellow Tang
Atlantic Blue Tang
2 false percs
leopard wrasse
painted wrasse
red parrot wrasse
2 sand gobies

I've seen absolutely no agression in the tank.

I'm off to class, but I'll check back in as soon as I get back.

 

[fishaholic911]

I agree with Rob I just lost a regal tang I had for 3 years. I think he was getting picked on even though he was with his tank mates for 6 months. There must have been an all out fight as 2 others were damaged. Anyways the regal acted just like your PBT.

 

[SWSaltwater]

Also if you had flatworms that were killed off by interceptor that could release poison. Did you remove activated carbon for the treatments?

 

[adamsky27]

Why are PBT's so difficult! They are one of my favorite fish, but such a pain!

 

[Satori]

Back from class.

Thanks for the replies, I don't think it was a fight; none of the fish have nipped fins or any sign of physical damage.

I haven't treated the flatworms in the fuge yet, and they look like the same numbers as before the interceptor, so I don't think there was any flatworm die-off.

I removed the carbon before the interceptor treatment, and replaced it after treatment.

My RO/DI is cranking out new water so I can do a water change in the QT. Remember, the water in the QT came out of the main tank tonight from a water change.

 

[fishyvet]

Could dissolved oxygen concentrations be an issue?

 

[Satori]

<a href=showthread.php?s=&postid=9302888#post9302888 target=_blank>Originally posted</a> by fishyvet
Could dissolved oxygen concentrations be an issue?

That's never been a problem. I have lots of flow (SPS tank) and have a skimmer. I leave the patio door open a little all the time.

 

[Satori]

Thanks for the replies everyone, but he didn't make it through the night.