Variety is not a nutrient and not really necessary for fish. Most of the high end pellets are what are considered to be a complete diet which makes feeding a variety pointless.
Think of it like your mixing up 5 different dog foods to feed a dog. Fish food like dog food are formulated to be complete diets so mixing in additional foods really doesn't help anything.
I still do provide some variety though, but not through the use of different pellets. I use carnivore sticks from yourfishstuff.com as a staple and supplement with freeze dried krill. This has proven to be my best combo this far and don't see it changing anytime soon.
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