2000 Annual Report for FS00-120
Cut Flowers: Tilapia Aquaponics Study
Summary
The production of Tilapia in tanks, within environmentally controlled buildings, has become a well-established, aquaculture enterprise in the Southern Region. There are currently twenty Tilapia producers in Virginia. They all raise the fish indoors, in tanks. It is illegal to raise Tilapia outside in ponds or raceways because there is concern about them escaping into the wild. Unlike many cold-water species, Tilapia can live in water that has heavy concentration of nutrients and bacteria. Their ability to withstand poor quality water makes them an ideal food fish for tank culture.
Even though Tilapia can live in poor quality water, the tank water does have to be cleaned constantly. Body wastes from the fish and leftover feed contaminate the water with bacteria, ammonia, phosphorus and other nutrients. Almost all of the producers use a re-circulating system with bio-filters to reduce the bacteria. It is difficult to remove the nutrients from these systems. Many Tilapia growers remove nutrients and enhance the profitability of these operations by adding production of hydroponic vegetables to the Tilapia tank system to remove nitrogen and phosphorus from the water. This kind of production is generally profitable during the off season but is generally not profitable during the summer months. When nutrients build up in Tilapia tank water, during the summer months, the waste water is often just applied to land.
The producer will use his producer grant to grow fresh cut flowers using the effluent from his existing Tilapia tanks from May through September. Fresh cut flowers generally have higher value than vegetables during the summer growing season. The market demand for cut flowers is strong in the Richmond, Virginia area throughout the Summer and Fall. Growing cut flowers in conjunction with Tilapia will safely reduce the nutrients in the tank water and will increase profitability of the operation by providing supplemental income.