I mainly have an AP system for the plants-veggies (I would enjoy it even if I didn't get to eat anything - if I just watched it, that beautiful mini-ecosystem) and don't intend to eat the fish.
So I don't care about FCR, what I need is how much waste the fish make. I don't need them to grow at all!
It turns out the above article says typically 50% of food is excreted by fish:! (yay)
That article wrote:
Even with careful management, some feed ends up as waste. For example, out of 100 units of feed fed to fish, typically about 10 units of feed are uneaten (wasted) and 10 units of solid and 30 units of liquid waste (50% total wastes) are produced by fish. Of the remaining feed, about 25% is used for growth and another 25% is used for metabolism (heat energy for life processes).
Backyard Aquaponics
