Stress

[Dale]

Hi Kevin.
Your tang could be experiencing stress for many reasons, some might be beyond your ability to detect (ammonia damage via shipping, internal parasites, severe mental distress etc...)
A couple of things to check first though:
pH
Salinity
Nitrates
Bully fish

After that think about your rock work. Does it provide ample spaces for the fish to swim behind and "feel" sheltered? If there isn't then the fish may need to flatten against the rock or jam itself into crevices to gain a feeling of safety. It then only has two choices - swim in the open unprotected or jam itself in the rock. Providing arches and back routes allows for a third option - sheltered swimming.

Next, you could try putting a screen in front of the tank, like big plants or something. Most fish become accustomed to looking out the glass at us but it must be a shock to some initially. When we approach the tank and peer in perhaps we look like large predators closing in. If I were a Tang I'd hide in the rocks too.

(This last ones just a guess)
You might try putting something on top of the tank too. I don't know about SW but many FW fish fear predators from above (birds) more than the side. I've noticed a dramatic change in behavior when I floated plants or driftwood on the surface of my FW tanks.
I don't know if any of this helps, just some thoughts.
Good luck with the Tang

[KrazyKuch]

Dale, I have a 230gal tank and I built a huge cavern on the one side for him to hide in and some slightly smaller ones on the other side aswell....It's hard to give him alot of hidden swimming space due to the fact that my tank is visible from both sides.

I have eggcrate on the top of the tank and my lights pretty much sit on top of that.

All my perameters are good...no ammonia, no nitrates, ph is at 8.1 temp is constant at 80 F and a SG of 1.0125

No fish bully him cause of his size....the next closest fish in size is probably 4", they just seem to swim in his cave to say hi and then leave again.

[X-Treme]

Originally Posted by KrazyKuch

a SG of 1.0125

PLEASE tell me that's a typo...

[G1GY]

Originally Posted by X-Treme

PLEASE tell me that's a typo...

I'll bet he meant 1.025.

You might want to bring that down to 1.023 or so so that it doesn't go above that when you have evaporation.

[KrazyKuch]

I have a auto top off with a 52 gal resevior...I have found that 1.025 is best for my acro's...I have had alot of success with my SG that high...

Yeah that was a typo I meant 1.025

[Dale]

Sounds like a nice set up
I also agree that a Q tank can be quite stressful as most are kept quite barren in case meds are needed. One advantage though is being able to run it dark (no stress to corals).
It sounds like you have acros but can you reduce your lighting period for a couple of days? Try running it dark when you are around and having the lights on for a short time when you are away. Or stick some cardboard on the the glass for a while (leaving some look through holes of course).
My experience with stressed fish is either they acclimate (sometimes slowly) or they give up the will to live and waste away quickly. The other thing to watch for is ich. It is an opportunistic parasite that can often show up in stressed fish.
A large blonde Naso is a beautiful fish - good luck again with him.

[EmilyB]

Nasos are so hardy and ready to romp. You have a skimmer running and good oxygenation I take it ? Feeding the fish nori, spirulina flake, mysis?

[KrazyKuch]

Yeah I have a huge beckett Skimmer
I feed nori, mysid,brine,krill, spirulina, formula 1, new life spectrum, ocean plankton, blood worms...And i think thats about all that i can think off

[KrazyKuch]

Well thanx all for the suggestions, but he passed away last night! May he rest in peace!

[muck]

Sorry to hear buddy.