I have watched that spot. First it was a marking, then it seemed to have grown a bit wider. Yet you can see it through the other side faintly... I have yet to see any irregular lumps onto the other side (which I will note I saw Admiral have, same area, just no spot). He had it since he was a lil' guy, about 6 months old. And obviously there is nothing you can do for tumors on fish so not much I can do.
And look at the picture of Spartan by the ship... I have noticed this too!! See the small bumps on the spot? That has been new since about 6 months ago. How fast do tumors progress anyways? I have yet to have a problem, which is good. He IS 2.5 years, so he has some years in him :) .... a few, not some, at least.
sorry for double post... but...
Here is a question!! Is the tumor genetic? Because I have tried breeding him once (his first time) which I expected not to turn out as it WAS his first time, as it was the female's. Because if it is I mind as well know D: Colors however has no problem, no spot, no lumps, nothing :) Both pretty darn healthy fishies.
Also, how do they get the longer tail on VT, like C.C has? His is enormously long. His nearly identical sibling brother has even LONGER fins!! yet he was not very...lively.