I'll try this one more time before abandoning the thread.
Industrial grade fishmeal (NOT for human consumption), is typically made from fish processing waste and low quality off grade fish that can't be otherwise used. It is often not made from whole fish, but fish parts.
Higher quality fishmeals are made from whole fish, but often fish of lower quality that can't be otherwise used.
Fish or fish parts are ground, dried and preservatives added to sustain a long shelf life. It may sit in a warehouse for many months until ordered by the fish food manufacturer. This processing and dry storage may render useless unsaturated fats and amino acids.
Because it's a dry meal, fish foods made from fishmeal require fair amounts of starch in order to bind the ingredients together. You will often see rice, wheat, oat or soy flour and/or gluten as the second largest ingredient by volume - sometimes it's the first largest! Even larger amounts of flour must be used for lower quality fishmeals as filler in order to increase the crude protein value in the crude analysis.
Fish foods made from FRESH FOOD GRADE WHOLE FISH (the same fish we could eat) require little/no starch as a binder because unlike powdered meal, fresh fish protein IS A BINDER.
Makaila misquoted the ingredients for NLS. NLS uses whole herring meal and whole krill meal. Although better than lower quality fishmeal because it's made from whole fish, it is still a meal most likely made from lower quality fish and it requires more flour as a binder.
I'm not saying that NLS is not a good food. I just don't think foods made with fishmeal are as good as those made from fresh whole food quality fish.
I have found fish foods that are made from whole fresh food grade fish and since switching to these I'm seeing less fish excrement. It is a bit soon, but I'm hoping to see improved health, color, growth, etc. with these foods over lower quality foods. Time will tell.
Footnote: I'm not selling anything here and have no interest in these fish foods. Merely reporting a discovery of awareness. Every fishkeeper is free to make his/her own choices regarding the foods they feed their stock.