Left Fin - not moving? (disease name?)

[chrissreef]

Baby onyx clown, has some white growth/thing at the base of his left fin which is causing him not to really use the fin and the fin just stays out.

Is this a parasite? bacteria? is it something he'll likely get through or is it required to pull him out? eating fine at the moment along with other fish. Thanks!

 

[TerryB]

Tough to say without a photo.

Terry B

 

[chrissreef]

here's two pics... white something near base of fin. thoughts? thanks!