What is going on with my palys!!!!

[dirland]

I have a 160 gallon tank and for the last 2 weeks my purple deaths and nuc greens are looking pretty bad. they are shriveled up and there mouth are showing. Has anybody had this happen, what could be the problem.

I am running GFO and bio pellets and I started dosing vitamin C about three weeks ago. All other zoos are doing fine and growing.

Tank parameters are as follows,

PH 8.1
ALK 9
calcium 420
salinity .025
nitrate 0

 

[Tenor]

Look like they are feeding. Anyway, your paly look good, they do that sometime.

 

[BuddyRo]

Yeah, mine have done that a few times and come back 150% better...

 

[dirland]

how long do they usually stay like that?