Aquaponics is the combined culture of fish and plants in recirculating systems. Nutrients, which are excreted directly by the fish or generated by the microbial breakdown of organic wastes, are absorbed by plants cultured hydroponically (without soil). Fish feed provides most of the nutrients required for plant growth. As the aquaculture effluent flows through the hydroponic component of the recirculating system, fish waste metabolites are removed by nitrification and direct uptake by the plants, thereby treating the water, which flows back to the fish-rearing component for reuse. In my system tilapia will be produced along with a variety of herbs, leafy plants, vegetables, and perhaps fruits.
The aquaponic system I will be utilizing is a scaled down version of the University of the Virgin Islands commercial scale system. It is roughly 1/8th the size of the UVI system, but may be multiplied in accordance with resources and demand.
The UVI system has been producing tilapia for more than a decade. It is a proven system and detailed information relating to it is freely available, including some of this text which I am, honestly, guilty of plagiarizing freely at times. Thank you Dr. Rakocy. I wish I could afford to go to the Virgin Islands and take part in one of your training programs, but I’ve got to do it the hard way.
Aquaponics has several advantages over other recirculating aquaculture systems and hydroponic systems that use inorganic nutrients solutions. The hydroponic component serves as a bio-filter, and therefore a separate bio-filter is not needed as in other recirculating systems. Aquaponic systems have the only bio-filter that generates income, which is obtained from the sale of hydroponic produce such as vegetables, herbs, and flowers. In the UVI system, which I copy, and which utilizes employs raft hydroponics, only calcium, potassium and iron are supplemented. The nutrients provided by the fish would normally be discharged and could contribute to pollution. Removal of nutrients by plants prolongs water use and minimizes discharge. Aquaponic systems require less water quality monitoring than individual recirculating systems for fish or hydroponic plant production. Aquaponics increases profit potential due to free nutrients for plants, lower water requirements, elimination of a separate bio-filter, less water quality monitoring and shared costs for operation and infrastructure.
The current version of my system can be found here.