Not Ich, at least not
Cryptocarans irritans type of marine ich.
Is it a hard tumor? Not sure. Can't truly "feel" it. It appears to be soft.
Is it fuzzy and soft like cotton? Outer portion of "hump" appears to be 'like cotton'
How long has the fish displayed this growth? First noticed growth just before first post about a week ago. I transferred fish, LR, ect to new tank on Thanksgiving W.E., a few days before growth first appeared. The only new item added to new tank was some pre-cycled sand. I reused about 1/2 the orig. filter media to expedite cycling.
Was the fish injured prior to the appearance of the growth? No. I don't think so.
How has the growth changed since you've noticed it? Its gotten bigger. See pics from 1st post vs. my last post. You can see its development.
What do you feed the fish? Frozen Brine Shrimp.
Have any other fish in your experience displayed this before? Nope. Other fish in tank is a Jennifer fish and it is totally normal.
Describe the fishes behavior for a day, how it eats, how it sleeps, how it swims, any unusual behavior. This Clown has always been hyperactive and still is. Seems to swim actively all the time (even with lights out). Both of the tank's fishes behavior has not changed. Both act happy/healthy.
Have you spoken to the LFS you acquired the fish from about this in any of their fish, and if they say yes (doubtful), what did they say about the fish that had this condition before? I bought the orig tank (a 12g Bio Cube) w/fish, LR in it. The storekeeper misrepresented its value and I paid too much. I haven't had contact with him since, but fish were healthy for 7 weeks before I moved them to a new Bio Cube 14 (old tank had sump light only for lid).
Have you treated the fish at all, and if so, what did you do? Please see my last post; short FW dip and direct application of Rid-Ich+ to the lesion.
Has the tank been used for fish or reptiles, etc. before?