Here are some better pictures IMO:
1. Do you have any other fish in the tank?
2. How long have you had the clown fish?
3. Have purchased any new fish within 2 months?
4. What is your water chemistry?
5. Does there appear to be red around the white object?
6. Does the white object have a texture similar to cotton?
1- Yes. 1 Yellow Tang, 1 Sailfin Tang, 1 Purple Psuedochromis, 1 Sixline wrasse, there is 1 other Oscellaris clown besides the one with the white thing.
2- I've had the clowns right around a month
3- I just added the Tangs last week.
4- The only levels that seems to be high are my PH and salinity. PH is 8.4 and salinity was 1.027 when I last checked a week ago, I'll test again today.
5- There doesn not appear to be any red spots
6- it looks more like flesh than cotton