BTA Dying, pooling, or eating?

[Sstadler]

Hello. I’ve had my BTA for approximately 3 weeks in an established mixed reef tank. Not sure if my BTA is dying, pooping, or eating? I walked in and caught him doing this for the first time. I feed him mysis every 3 days. Today was one of those days.

parameters:
PO4 - 0
Ca - 430
Alk - 7.7
Mag - 1375
pH - 8.0
Ammonia - 0.0
Nitrite - 0.5
Nitrate - 0
Temp - 78.0

I attached photos of affected BTA and a before pic

 

[Jason mack]

Have you been feeding it ..its probably having trouble digesting....its got good color and it's still attached ...I'd say its pooping ...

 

[Sstadler]

Have you been feeding it ..its probably having trouble digesting....its got good color and it's still attached ...I'd say its pooping ...

yes mysis once every 3 days. And yes color is still pretty normal

 

[Jason mack]

I dont feed my anemones ...only what they get from the water colomn

 

[D-Nak]

Stop feeding it and see if it stops deflating. If it deflates regularly during the day, I'd be concerned. If only at night or after eating, I wouldn't be concerned.