What is Aquaponics

Aquaponics is a bio-integrated system that links recirculating aquaculture with hydroponic vegetable, flower, and or herb production.
In aquaponics, nutrient-rich effluent from fish tanks is used to fertigate hydroponic production beds. This is good for the fish because plant roots and rhizobacteria remove nutrients from the water. These nutrients, generated from fish manure, algae, and decomposing fish feed are contaminants that would otherwise build up to toxic levels in the fish tanks, but instead serve as liquid fertilizer to hydroponically grown plants. In turn, the hydroponic beds function as a biofilter, stripping off ammonia, nitrates, nitrites, and phosphorus so the freshly cleansed water can then be recirculated back into the fish tanks. The nitrifying bacteria living in the gravel and in association with the plant roots play a critical role in nutrient cycling; without these microorganisms the whole system would stop functioning. Aquaponics serves as a model of sustainable food production by following certain principles:

  • The waste products of one biological system serve as nutrients for a second biological system.
  • The integration of fish and plants results in a polyculture that increases diversity and yields multiple products.
  • Water is re-used through biological filtration and recirculation. Local food production provides access to healthy foods and enhances the local economy.

In an aquaponics system, fish eat food and produce waste (mainly ammonia). Ammonia is hazardous to fish, even in small quantities (.04 mg/l) and toxicity increases in relation to pH and temperature. Ammonia (NH3) is food for beneficial bacteria (Nitrosomonas) which turns it into nitrite (NO2) waste and then another type of beneficial bacteria (Nitrobacter) turns the nitrite into nitrate (NO3) waste. Nitrate is less harmful to fish. The nitrate, phosphorous, and potassium are food for plants/algae which remove these from the water the fish live in. This is known as the “Nitrogen Cycle”. When the system is in balance, the water will be crystal clear and ammonia and nitrite levels will be zero.

A small almost portable Aquaponic system that, even at a small scale, can be very efficient.

    Advantages of Aquaponics

  • Environmentally responsible with low water usage and low power usage.
  • The primary inputs to the system are fish food and water.
  • Little to no chemical usage. Aquaponics requires no synthetic fertilizers and few pesticides.
  • Many of the plants that thrive in Aquaponic growing are very easy to grow.
  • Low susceptibility to pests and diseases.
  • Timely crop turn around.
  • Increased crop production per square foot versus traditional farming.
  • Multiple crops and fish can be grown from the same system.
  • Fish can be harvested as an additional food or revenue source.