Replacement for FAA

Urine is a high nitrogen content liquid fertilizer that could be used, i would also think that FPJ made from legumes would be high in nitrogen also or other high nitrogen plants like corn or comfrey but i don’t think any of them will be as rich as FAA or urine. You could also plant legumes in with your crops such as hairy vetch, Legumes r known to pull nitrogen out of the air and store it in small sacks on the roots that the soil bacteria have access to and release to the plants.