3 Aquaponics Systems
One of the striking benefits of aquaponics is its flexibility. As long as the plant, fish, and bacteria components are healthy and balanced, the system can be arranged in many different ways. If the ratio of plants to fish is managed carefully, aquaponics systems can easily be scaled up or down. Each aquaponics arrangement offers its own advantages, meaning that a system can be built to suit most climates, spatial requirements, and preference of the farmer. Below are the three most commonly seen schemes, followed by a visual.
Nutrient Film Technique
The Nutrient Film Technique, or NFT, holds plants suspended inside narrow tubs or pipes. A thin layer or water can flow into the tubs and graze the roots that are suspended inside the tubs. A significant advantage of NFT aquaponics is that the tubs are light, so they can be arranged vertically and thus optimize space. Because of this, NFT systems can be applied in indoor aquaponics farms effectively (Rakocy et al., 2006).
Media Filled Beds
Media filled beds resemble traditional plant pots, but the plant roots are placed in a non-soil medium such as gravel, pearlite, or sand. Culture water is pumped through the medium until it is saturated, so the roots have access to the nutrients in the water. The media used in the beds can filter particulates out of the water effectively, but this system is harder to scale up due to the weight of the media (Balcom, 2015; Rakocy et al., 2006).
Raft
In raft aquaponics, the plants are contained by a polystyrene raft floating on the water, and the roots are completely submerged in the culture water. Since the polystyrene raft covers almost the entire water surface, light does not penetrate into the water. This helps maintain water temperature, especially if the system is run outdoors in a tropical climate, and also prevents algae growth (Balcom, 2015; Rakocy et al., 2006).
References
Balcom, P. (2015, July 31). Irrigation and Aquaponics—Technologies to Improve the Quality of Life in Developing Nations. WISE Journal of Public Policy. Retrieved September 21, 2016.
Rakocy, J. E., M. P. Masser, and T. M. Losordo. 2006. Recirculating aquaculture tank production systems: aquaponics – integrating fish and plant culture. SRAC Publication 454:1–16