Something doesn't add up for me. I read the nutritional breakdowns on prepared foods, and they are good.Okay, fair points. Why do people feed fry live foods if the prepared foods have more nutrients?
But while I am in the world of anecdotes, I see a huge difference in results with live foods. If the very best prepared food I have ever found, bug bites flakes, gives me under 50% of the eggs live foods do, and other big name brands give even less, something is off. This has happened for decades, to the point where food preparation is a serious element in how I keep fish. Remember, I enjoy breeding my fish. Flake is for fish I'm not trying with.
A lot of my fish look at the best of flakes like I look at Costco lasagna. It just ain't right to them, and how palatable it is is probably part of it. So are all the small elements of nutrition that aren't on the label.
I don't feed frozen daphnia to my fish because while they are appealing live, they are a lot of shell dead. Mosquito larvae are the bomb though.