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The aquaponic system design channels nutrient-rich water from the fish culture system through plant beds in direct contact with the roots to effectively feed the plants. In turn, nitrogenous waste is removed through uptake by the plants for growth. Thus, the water is effectively cleaned and ready for reuse in fish culture.

Aquaponics (AP) is a self-supporting food production system that combines recirculating aquaculture with plant culture in the absence of soil (hydroponics). High-volume fish production results in nutrient-rich water that can be used to provide nutrients for plant cultivation.

Development of aquaponic systems resulted from the need to reduce costs associated with high-nutrient effluent discharged from recirculating aquaculture systems (RAS). Known for intensive aquaculture, RAS can produce large quantities of fish in a small volume of water. Some water is discharged and replaced in the system over time, as solid waste and toxic nitrogen by-products (ammonia (NH3-N), nitrite (NO2-N), and nitrate (NO3-N)) build up. Concentrated discharge from intensive aquaculture is a barrier to positive consumer perception of aquaculture. However, these accumulated nutrients can be similar in composition and concentration to hydroponic nutrient solutions and often exist in the form preferred by plants (Rackocy et al. 2006). Combining these two production technologies provides an efficient and sustainable method of growing fish and produce.

Hydroponics and intensive RAS each have ecological and economical drawbacks when considered individually. Hydroponic crops rely on chemical fertilizers that are expensive, hard to source, and in some cases are derived from rapidly disappearing natural resources. In intensive fish production, concentrated wastes are generated (i.e. effluent) that require expensive treatment methods, leading to poor consumer perception regarding environmental impacts. The high initial investment may be prohibitive to potential producers, as well. Aquaponics provides the opportunity to utilize aquaculture effluent while growing plants with a sustainable, cost-effective, and non-chemical nutrient source.

The integration of fish culture and plant production can provide several opportunities for farmers or producers, including sustainable agriculture, marketing versatility, and generation of multiple income streams. Environmentally, plant growth and yield in aquaponics can meet, or in some cases surpass, output values of either hydroponics or soil-based agriculture (Pantanella et al. 2011, Savidov et al. 2005). The shared core concepts of efficient water and land use, the ability to intensify crop production year round, and use in geographic areas not suitable for traditional agriculture has driven a recent increase in the popularity of aquaponics (Somerville et al. 2014).

While production values have been shown to be similar to both hydroponics and RAS (Pantanella 2013, Savidov et al. 2005), the integration of these systems can make it more difficult to manage. Many groups interested in aquaponic production are deterred by the high start-up cost and lack of proven models for success. Understanding that aquaponics is a complete ecosystem is essential to provide correct conditions for fish, plants, and bacteria, which are the three major groups of organisms that drive AP systems.