Aquaponics: Fish Waste to Human Food

AquaponicsDid you remember to feed the fish? The tomato plants have been looking a little lackluster lately.

Aquaponics, or combination of soil-less hydroponic plant-growing with aquaculture and the cultivation of aquatic creatures, is a sustainable food production technique that uses fish waste for plant fertilizer.

Fish raised in indoor tanks or outdoor ponds use the little fishes’ room. Waste from the fish tanks is collected, broken down by helpful bacteria, and flushed into the hydroponics portion of the system where the fish poo provides a rich source of nutrients to plants either in containers, floating on foam, or on bamboo rafts. Water filtered by the plants then returns fresh for all the fish.

Practically any type of tasty green vegetable and a wide variety of freshwater fish species can be cultivated. Tomatoes, salad greens, beans, potatoes, tilapia, or trout – under such circumstances the imagination lends itself firstly to fresh fish and chips perhaps, without ever leaving the comfort of home.

Aquaponics describes a wide range of combined methods -— a surf and turf variety of self-contained artificial little ecosystems engineered for food production purposes. Since pesticides and chemical fertilizers would be hazardous to the health of the fish, the whole system lends itself to natural, organic food production.

Aside from a place for plants and fish to grow, and maybe a heater, just a few other things are needed. “Beyond the tank and bed, each system relies on the following customizable components: a solids removal area, a biofiltration system to grow helpful bacteria that break down the fish waste, a water sump and pump, and an aeration system,” Oregon State University Extension Service reports.

To raise tilapia and many other fish, you’ll likely need a transport permit from the Oregon Department of Fish and Wildlife. Apparently “for personal use” isn’t an excuse here, but the permits are easily obtained online.

Hooked on aquaponics? For more information check out Oregon State Extension’s aquaponics web page at, or the U.S. Department of Agriculture’s page at

By Matthew Hunt