Fin to Flower & Aquaponic Basics
Aquaponics is a millennia old process for farming both plants and fish, and may represent one of the best technologies every devised for sustainable, environmentally friendly, food production. We bring this fascinating technology to a size that is appropriate for anyone, and reproduces the symbiotic relationship between aquatic life and plants on your counter top.
Aquaponics, in the simplest terms, is a combination of aquaculture (fish) and hydroponics (plants grown in water). Water provides a living environment for fish and plants, with the plants feeding from waste products of the fish and helping keep the water system clean. With a continuous supply of quality nutrients, and with proper lighting, plants in aquaponics systems have been recorded to grow at 3 to 15 times as fast as soil grown plants. Aquaponics systems have been in use for thousands of years, mainly in large scale applications for farming and food production.
Regardless of size, the basic operation of aquaponics systems is the same. Fish waste breaks down into ammonia, and bacteria in the system then breaks the ammonia down into nitrite. Bacteria then breaks the nitrite down into nitrate. The elements in the nitrate serve as nutrients by the plants. The water in the system is continuously cycled, carrying nutrients to the plants and clean water to the fish. This is the Nitrification Cycle, and it is essential to a properly operating system.
The Nitrification Cycle
Without the Nitrification Cycle in operation, the system will quickly become overloaded with ammonia. Even at low levels, ammonia is toxic to fish. The nitrites produced by the first nitrification is also toxic to fish, but these will be quickly converted into safe nitrate.
The key element to the Nitrification Cycle is the Nitrifying Bacteria. These bacteria, once established, will live invisibly on every surface of the system and will be extremely effective in breaking down ammonia. However, these bacteria must be allowed to develop naturally in the system so they are properly adapted to the system’s unique water conditions. It will take the nitrifying bacteria about 4 to 5 weeks to grow and fill the system. This process is only necessary once, when the system is first started.
Another important water quality factor is acidity, measured in pH from 0 (highly acidic) to 14 (highly basic or alkaline). Ideally, the water acidity should be neutral, about 7 on the pH scale. Initially, pH level is determined by the water used to fill the system. Municipal water is very close to 7 pH, very suitable for an aquaponics system. However, as the system operates, the pH level can change. Ammonia from fish waste will tend to raise the pH (making the water more alkaline), and compounds like carbon dioxide can lower the pH (making the water more acidic). Again, the Nitrification Cycle comes into play, controlling ammonia in the water and working against a sharp increase in pH. In a properly operating, large system, water pH will be kept reasonably under control by the natural processes of the plants, animals, and bacteria in the system.
A properly designed and maintained system replicates the symbiotic interactions of aquatic life, plants, and water that occur continuously in nature. With proper setup and maintenance, aquaponics is a highly sustainable, interesting, and rewarding operation.