In a closed-system method of aquaculture, fish waste accumulates in the enclosure which, if not treated, pollutes the very water the fishes swim in. This unclean environment adversely affects the growth and health of the fish. Coincidentally, the dissolved wastes that pollute the water are the same nutrients that terrestrial plants need to grow healthy. This is where the science of aquaponics come in.
Aquaponics is the combination of aquaculture and hydroponics. In essence, water from the fish tank or pond is pumped into beds of edible plants growing in a soil-less media (like pea gravel or other suitable materials). After the plants absorb the nutrients from the water, the filtered water is then returned into the tank or pond. This cycle is repeated at regular intervals.
As a result, the plants and fishes benefit from each other, grow healthy and in no time ready for harvest.
A sketch of possible aquaponics set-up in the farm.
I believe this is one project worth looking into. Incorporating this system into the farm would be a blessing to the fishes in the ponds and would provide a healthy source of vegetable produce.
My only concern is that the system requires a pump to constantly circulate water from the fish tank (or pond) into the plant beds. This would require the use of electricity and unfortunately electricity in our location costs more than gold [exaggeration fully intended].
For a brief discussion into aquaponics click here to watch this short presentation in YouTube.