I mix about 4 different types of food into a container and feed my fish from it. Is that bad, mixing foods? Can you think of any drawbacks? It's just super-convenient for me
I think it could be bad in situations where you have picky fish, in which case they'll just eat the stuff they like out of the mix and not touch the rest which leads to water pollution. If your fish eats up all the food then it's ok.
I do that with all the little sample sizes of fish food I win at raffles. I'm due for a consolidation of samples, I like to use up a mixed container instead of continually dumping food on top, as the food on the bottom just sits there.