This morning around 7 am I noticed a small white bubble looking thing on my fish behind her fin. However, when I got home from work around 5 pm, it didn't look like a bubble anymore. It looks more like a flake. (Its almost similar to when a person has a sunburn and their skin starts to peel) It hasn't multiplied and she ate fine this morning and has been acting normal this evening, but it still concerns me. I tried to get a good picture.. Any thoughts or advice???

-I have a 29 gal biocube, its saltwater
-Salinity is at ~1.020
-Ammonia is at 0
-Nitrate is at 2
-Nitrite is between 0-0.05
-Water temperature is a high (its been a struggle keeping it down) it ranges in the high 70s

-I have a 29 gal biocube, its saltwater
-Salinity is at ~1.020
-Ammonia is at 0
-Nitrate is at 2
-Nitrite is between 0-0.05
-Water temperature is a high (its been a struggle keeping it down) it ranges in the high 70s