My feeder comets have changed color dramatically—well mostly all have lost the cute black accents they used to have. One was almost black and faded to bronze. Another had black fins on an orange body it's just about all orange now.
I had a sarassa with an orange hat on its head, it faded away and now it's all white.
I never fed them at all until just recently. The foods say they enhance color but I can't say I've seen any difference, other than the algae growing more...
I started with the Tetrafin flakes and now feed them Topfin floating pellets. I saw the Higari brand for twice the price, but the ingredients appeared to be about the same. I recently read that phosphorus content is something to look at for water quality... Whew! I don't even know what fish food to buy...