Which specific ingredient in fish food enhances color in fish?

So I been thinking... I see different kinds of fish food (pellets, flakes, live food, etc.) for sale from different companies with different ingredients. Which ingredient specifically enhances colors in fish? For example, is it the protein % or spirulina or whole fish? A perfect analogy of this is dog food. You get what you pay for. I feed both of my dogs grain-free and their coats are soft and shiny. I don't want to feed my dogs the food made by Pedigree or Purina, that is full of fillers and by-products. The same goes for ANY pet under my care. Fish food doesn't seem that expensive compared to dog food so I want to feed the best brands out there. So far from my research I have found that top brands include New Life Spectrum, Omega One and Hikari.

 

In my Omega One, Color micro Pellets it says on the side that the Salmon skins Provide a Natural Color Enhancement, and on My Omega One Super Color Cichlid Pellets again its the Salmon Skins

 

So basically its anything that provides omega-3s, assuming that's why they have the salmon skins in there?

 

So basically its anything that provides omega-3s, assuming that's why they have the salmon skins in there?

I'm not sure could be the side of it says that its rich in Omega 3 and 6 Fatty acids for strong immune systems, but if salmon skins have omega 3 in them than that may be so

 

Here is a pretty good read on how foods enhance color. In my understanding it is dictated by the fishes chromatophores utilization of carotenoids.

 

MattB, Thanks for the link. I bookmarked it for future reference. Nice list of food for plecos too. Alison

 

Thank you for the very informative post, MattB. So I'm pretty much going to look for krill, spirulina, and astaxanthin in the ingredient list whenever I buy fish food from now on lol.

 

I'm not a fan of using colour enhancing foods exclusively, one of my Lfs used some for their ember tetras & they all developed random black markings, once they stopped & fed a variety of other foods the black marks disappeared & the embers had their lovely colour back.

 

Well they do recommend you feed a variety of foods. So maybe rotate between brands and color enhancing food and "normal" food. When I feed my dogs, I change the flavor every new bag and switch brands at least every six months so they get a variety of protein sources.