I read it can be made from fish waste which doesn’t sound good. It’s in one of my fish food pellet ingredients.
Fish protein concentrate and fish hydrolysate | Feedipedia
www.feedipedia.org
Thanks for the reply. That sounds awful ! Lol I wouldn’t feed my fish feces even if they would eat it. Nor would I want to feed my bichir any kind of fish that ate feces as their main diet because it would transfer.