large white spot on gill

[koa79]

I have a X-large purple tang that has a big white spot on one side of his gill and body about a inch round. I have had this fish for 2 years now and he still eats like a pig and very active. What could it be??

 

[koa79]

 

[TerryB]

Possibly a wound with a bacterial infection. Was the fish netted recently. I would try a large water change using well aged and aerated saltwater first. If you can get some Beta glucan then add a little to the food for a few days. If the fish is getting worse then you should use a good antibiotic in quarantine.

Terry B