Purple Encrusting Monti Sick??

[klaeq]

I go this purple encrusting monti about 2 weeks ago. The first pic is what he looked like for the first week and a half. You cant really see, but he is a nice deep purple color. He was doing good for almost 2 weeks, and I had to go out of town for 3 days. The next 3 are what he looked like when I came back from a 3 day business trip. My roommate fed my tank per my instructions, and I took measurements before I left and when I came back. Here is what I am at:
Temp: 81
Salinity: 1.025
PH: 8.2
Alk: 1.7-2.8
dKH: 8.3
Calcium: >450
Ammonia: 0
Nitrite: 0
Nitrate: 0
I'm not sure what is going on. Can someone please tell me if I lost this or not? He is turning white, and has some white spots with little feather looking things growing on him. I no longer have a QT because it cracked and I haven't had the time to get a new one. Thanks for your help guys.

 

[jmick]

Monti eating nudis would be my guess and if that is the case consider it toast.
Oh yea, on a second look there they are. This is a very very tough critter to get rid of and if you have any other monti's check them to make sure the nudi has not moved to other corals. I consider any coral with them to be doa and remove asap...you can not really treat for them and removal is difficult.

 

[jmick]

Side note, if the piece is large enough you can try to cut off the effective pieces and scrub the surrounding rock using a lot of elbow grease (anywhere you see the nudis has to go and look for eggs as well). I have also read the radiant wrasses will eat nudis.

 

[klaeq]

Thanks for the advice. Unfortunately, I had to get rid of the coral all together. The nudi's spread too much for me to try to save the piece. Thankfully they were localized on this piece and not anywhere else in my tank.