I see you guys are discussing various fish foods and thought that I would try to help out.
Protein is used to replenish and build muscle and tissue. Protein in excess of 40% is passed by the fish. I can dig up a study if you don't believe me.
Protein digestibility is the percentage of the protein that your fish can use. Most of the protein in your fish food should come from whole fish meal (around 92% digestible protein). Fish parts meals like salmon or catfish should not be used. Fish carcasses don't have much highly digestible protein.
Fat is the form of energy that can be stored. Excessive fat or in better terms excessive energy in the fish's diet is stored in the liver. Females need fat stored in the liver to produce eggs.
Starch is a carbohydrate form of energy that cannot be stored. Starch that is not used as energy is harmlessly passed.
Sugar is a carbohydrate form of energy that cannot be stored.
The order that energy is used first to last: 1. Sugar 2. Starch 3. Fat
Fiber is also a carbohydrate. Fiber aids in digestion. Excess fiber is passed harmless into your pond.
Minerals need to be replenished as they are used. Excess minerals are passed harmlessly into your pond.
Moisture is water content.
Example:
XYZ GameFish Food Honestly this will work for any carnivore
Protein - 39%
Fat - 11%
Starch and Sugar - 27%
Fiber - 3%
Minerals - 10%
Moisture - 10%
Total Energy(fat, starch and sugar) 52
11% Fat x 2.25 = 24.75 + 27% Starch and Sugar = 51.75
In the worst case your fish might pass some starch and store all of the fat. The big advantage in my mind anyway is plenty of stored fat for females to produce a bumper crop of healthy eggs.
I hope this helps.
