We converted a dairy barn in Wisconsin to fully indoor (no outside light, light dep by today’s standards) Nelson Pade aquaponics system.
4x 250 gallon talapia tanks feeds (no devils) lettuce to three schools in the local area.
We grew a hemp plant (cherry wife) to flower in 2017 on 2-400ppm. He wasn’t supposed to grow it, but we had space to drop in a plant so we just went with it.
So I can say it totally works, but those systems are quite complex with all the equipment and filtration for a closed loop cycle. Pretty expensive, like a $250,000 install. Haven’t seen anyone grow cannabis plants commercially from talapia yet using Nelson pade aquaponic systems. Would love to see it happen!
Edit: wanted to add that it takes a lot of (properly managed) fish to poop and make high enough ppms for the nutes to matter.
I just heard back from the founder of our company, who retired last year concerning humic acid and animal health.
The USDA researched this subject. Their concern was poultry or other small animals. Fish would more than likely qualify as a small creature. The problem here is that there are such a wide variety of molecular sizes when it comes to humic acid that could overload kidneys in small animals. It also depends on the actual source of the leonardite, which may introduce free heavy metals. Cattle and large animals should likely not be affected by having larger organs to filter out unwanted or dangerous substances from improper chemical extraction.
As a side note- AGT-50 is water extracted and any heavy metals (in ppb) are chelated, which prevents bio-accumulation.
My bro Marty waddell has an amazing cannabis aquaponics channel on YouTube… Super smart muthafucka and super smart about beneficial insects and biology shit!