Kole Tang - stopped eating

[JJ70]

Tank is 6 months old. My Kole Tang of 2 months all of a sudden stopped eating 3 days ago. I have no clue as to why. Now he hides out in the rock work and swims slowly around the back of the tank. He shows no visible signs of disease, only lethargically swimming. I've tried all his favorite foods and nothing. Other fish include a pair of clownfish along with a cleaner shrimp and snails. I did clean some cyno off the sand (2" depth) and moved a 6105 a few inches right before he started acting funny but nothing else looks out of the ordinary that I can tell.

Water Parameters:
Alk: 10.0
Cal: 390
Mg: 1220
PH: 8.1-8.3
Temp 78.5 - 79.5
Nitrate: 5.0
Phos: 0

I run a GFO reactor along with a skimmer.

Any ideas?

[Newsmyrna80]

Obviously ammonia is at 0, correct? Have you added anything to the tank recently?

[JJ70]

Yeah sorry. Ammonia is zero and no new additions to the tank.

[Kworker]

Any new additions to the tank?

[snorvich]

The reclusive behavior and the time line is concerning. How was the fish quarantined?

[JJ70]

He was QT'd for 11 days before placing him in the tank. The Kole and clownfish were first fish. QT'd separately. I put them in a few days early because we had company arriving for the summer and my wife wanted something "moving" in the tank.

[snorvich]

He was QT'd for 11 days before placing him in the tank. The Kole and clownfish were first fish. QT'd separately. I put them in a few days early because we had company arriving for the summer and my wife wanted something "moving" in the tank.

11 days is not meaningful. Was the fish acquired from a source that runs copper in their system (most online vendors do). Does the fish hang out near where water returns to the tank?

[JJ70]

It was a LFS. They do run copper though (all tanks plumbed separately).

No he actually hangs out either in the rock work or near the bottom of one of the corners. I have high flow in the tank though overall. This will probably be my first fish loss ever. Sucks.

[Newsmyrna80]

All is not lost yet. Due to the timeline you could be dealing with Brook, velvet, internal parasites or even a bacterial infection. Lethargy and suppressed appetite are common in those diseases. You will need to get the qt going. You have 2 choices and are really based on the outcome of research as to whether you are dealing with 1. something highly contagious (Brook,velvet) or 2. something relegated only to the tang (bacterial or internal parasite). If you believe 1 then you need to quarantine both fish and leave your main fallow. If 2 then quarantine the Kole by itself and treat.
Are there any other symptoms? Can you post a pic?

[JJ70]

Update

Could never catch the Tang to QT due to the rock work so I was waiting for him to die. The funny thing is he was not ready to die and has started to make a come back!!!! He showed himself yesterday and swam out in the open and ate a little today. Still no outward signs of disease. Hope he makes it.

[FortyFour]

Did he make it?

[JBeursken]

I'm having the same problem with my Kole Tang....He just started acting weird...although I did notice a Green Algae on the bottom of my tank with purple spikes on the side...came out of no where....