Color fading?

[cocoacf]

I've got two relatively small clownfish.. I've had them for about two months now. They were about an inch or smaller when I got them, and have since grown at a steady pace. Recently though, the smaller one has started to have the colors around his tail fade; mostly the black on the end of the tail. The other clown fish has vibrant colors, as well as my pygmy angel fish. I'm just curious about the smaller one? The rest of his colors seem to be fine.
I've heard what you feed them helps keep the colors good. I feed them two different types of food, that I switch up every now and then.

 

[blayz77]

hard to say for sure if its anything or not, but i noticed with my two little clowns that were also about an inch, that one was dark and vibrant and very active and one looked a little faded and had the belly fins tucked in.
i have them seperated now since i am treating one. but i noticed this morning that the one that was a little dull and seemingly shy now is nice and dark and has the fins flared out.
so im guessing mayby one was intimidated by the other or soemthing they never appeared to fight or anythign but one is a really agressive swimmer and would like bump into the other kinda like hey get outta my way kinda thing.
could always give em time apart and see what happens, ive been told color fading can be due to stress.
ill have to see how mine act when i put em back into the same tank, see if that one tucks his fins in again and stuff.