Introduction To Aquaponics

An aquaponics system is made up of plants, fish, bacteria and worms working in harmony to grow vegetables. It is a closed system that is virtually self contained. Aquaponics is basically a cross between aquaculture (fish farming) and hydroponics, without the associated problems. Before I get into more detail on the subject I will first cover aquaculture and hydroponics. The intensive environment in aquaculture tanks is cruel and results in environmental problems. Overcrowded fish means significant quantities of waste, which releases harmful compounds that increase in concentration very quickly. Because of this, a substantial percentage of the water in the tanks must be discharged and replaced. This leads to very heavy water consumption and in many cases the discharged waste finds it way into waterways, thereby polluting them. In hydroponics plant feed is supplied by costly artificial minerals, chemicals and trace elements. This is an unwholesome growing environment and makes plants susceptible to root rot. This liquid plant feed requires changing frequently in order to replenish nutrients and stop the chemicals and mineral salts building up to unsafe concentrations. As with aquaculture a significant amount of water is used for discharging effluent from the nutrient tank, and environmental contamination is therefore an issue The plants derive their food from waste, and the water is subsequently recycled by beneficial bacteria. Solid fish waste gets recycled into a rich plant feed by a process involving worms. These living components come together to create a system that is largely self-supporting. The water is re-circulated through the vegetable beds and allowed to drain back to the fish tank, and the only additional water used is for topping up water lost by evaporation and plant respiration. This adds up to a healthy environment for both fish and plants where health problems are rare. The nutritive elements found in waste have to be processed before the vegetables can utilise them. This processing is carried out by bacteria living in the grow beds and is referred to as the nitrification cycle. There are a number of types of aquaponics system, however flood/drain systems are the best system for a beginner. A flood/drain system is the most simplistic kind of system, and it is straight forward to assemble and maintain. Versatility and simplicity are the definitive characteristics of this type of aquaponics system In flood and drain systems, raised grow beds full of growing medium are used for producing vegetables. These beds are initially flooded with water from a tank containing fish. Once the beds are full, the water drains back into the fish tank. This repeated flood and drain is repeated continuously and is controlled either by an auto-siphon or a timer. By allowing the grow beds to fill up and then empty, the plants are supplied with food and their root systems are subsequently oxygenated. This is similar to natural ebb/flow systems that occur naturally; as a matter of fact this type of aquaponics system is often known as as Ebb and Flow instead of Flood and Drain. I will briefly go over the other types of aquaponics system: Continuous Flow Systems - water from the fish tank is continuously pumped into plant beds, so there is a continual stream of water through the growing medium. Nutrient Film Technique Systems - water from the tank runs in a thin layer through specially designed gutters. Plants in net pots are situated in these gutters, and their root systems trail in the water. The types of vegetables that can be produced with this kind of aquaponic system is restricted to leafy greens. Deep Water Culture Systems - The vegetables grow with their roots in the water, supported by floating rafts. Aquaponics is a lot less labour and time intensive than other types of gardening. Feeding and irrigation are completely automated. Weeds are unable to get a footing, so weeding is eliminated. The grow beds are waist high, which is good for your back and helps keep animals from reaching the plants. Low cost fish food is used instead of costly liquid fertiliser. Expensive monitoring is not required, and only simple occasional tests need to be done. Aquaponics is an entirely organic gardening method. As it happens, this is the most prolific kind of organic gardening system. If not kept entirely organically, the living organisms that it contains will be harmed. The most remarkable attribute of aquaponics, however, is the superior plant growth .