Sick Gold banded maroon (please please help)

[luisprado]

2 days ago my GBM lost his appetite and started moving sluggishly. Yesterday she wouldn't swim around and just stayed on her anemone. Today when my light came on I noticed her gold patches looked faded and she had some with fuzzy looking things in her head and tail area. Can anyone tell me what she has and if it's curable? I've had her for more than 2 1/2 years and it's breaking my heart to see her like this.

Here are my water params and log of what I've done lately.

PH 8.1
Ammo = 0
Nitrites = 0
Nitrates = 0
Salinity =1.025

I did a water change on Monday but no more than the usual 10%.

[Slakker]

no new corals, fish, or anything else?

[luisprado]

No new corals in over 8 months and no new fish since about a year.

[Slakker]

What are you feeding?

[luisprado]

Once a week I feed mysis shrimp and twice a week I feed tetramin tropical crisps. I've been doing this for over a year.