I think if a person wanted to dive into feeding fish, a whole book could be written on it, and by the time they are finished writing the book, it would have to be changed because of the new things that are being developed or discovered.
Cliff notes:
Small fish need a different protein/fat/supplement additive than adult fish.
There is a huge difference between supplementally feeding fish and using enough food that the fish food is the majority or all of their diet.
Different species of fish have different nutritional requirements.
Here is a picture of Hybrid Bluegills. I did a test 2 years ago. Same number of HBG in 3 different cages. All fish came from the same supplier, and were of the same random size when placed in the cages at the start of the test. Each cage was fed the same amount of food, at the same time of day, for the same amount of time. This test was a 90 day test. This test is the reason why I switched to Optimal.
The write up of the test can be read here:
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=423360#Post423360 Plus here are a few things that I learned and observed in the past 2 years since switching to Optimal:
Ponds have less problems with FA. (I am guessing that more of the food is being utilized/absorbed by the fish and less is getting pooped out as fertilizer for FA/Plants.)
Fish survive stress better. (I observed a summer fish kill at a hatchery where they were doing a fish food test with fish in cages. The cages where the fish were being fed Optimal had approximately 80%-90% LESS dead fish in them than all the other cages, and IIRC they were testing 3 or 4 different mfg. foods in addition to Optimal.)
Fish fed Optimal seem to have more vibrant colors.
Redear Sunfish eat Optimal Bluegill food and I have also been told that Crappie have been caught in one pond with Optimal Bluegill food in their stomachs.
Another forum member here who has done a lot of fish feeding noticed that to get equal growth rates of sunfish he had to feed 60# of Aquamax vs. 40# of Optimal Bluegill food.
I am probably forgetting some things, but that has been my observations.
