There are several ways to design an Aquaponic system. The simplest approach is to duplicate a standard system or scale a standard system down or up, keeping the components proportional. Changing aspects of the standard design is not recommended because changes often lead to unintended consequences. However, the design process often starts with a production goal for either fish or plants. In those cases there are some guidelines that can be followed.
Use an Aquaponic system that is already designed. The easiest approach is to use a system design that has been tested and is in common use with a good track record. It is early in the development of Aquaponics, but standard designs will emerge. Standard designs will include specifications for layout, tank sizes, pipe sizes, pipe placement, pumping rates, aeration rates, infrastructure needs, etc. Using a standard design will reduce risk.
Design for available space. If a limited amount of space is available, as in an existing greenhouse, then that space will define the size of the Aquaponic system. A standard design can be scaled down to fit the space. If a scaled-down tank or pipe size falls between commercially available sizes, it is best to select the larger size. However, the water flow rate should equal the scaled-down rate for best results.
The desired flow rate can be obtained by buying a higher capacity pump and installing a bypass line and valve, which circulates a portion of the flow back to the sump and allows the desired flow rate to go from the pump to the next stage of the system. If more space is available than the standard design requires, then the system could be scaled up within limitations or more than one scaled-down system could be installed.
Design for fish production. If the primary objective is to produce a certain amount of fish annually, the first step in the design process will be to determine the number of systems required, the number of rearing tanks required per system, and the optimum rearing tank size.
Although the design of Aquaponic systems and the choice of hydroponic components and fish and plant combinations may seem challenging, Aquaponic systems are quite simple to operate when fish are stocked at a rate that provides a good feeding rate ratio for plant production. Aquaponic systems are easier to operate than hydroponic systems or recirculating fish production systems because they require less monitoring and usually have a wider safety margin for ensuring good water quality. Operating small Aquaponic systems can be an excellent hobby.
Systems can be as small as an aquarium with a tray of plants covering the top. Large commercial operations comprised of many production units and occupying several acres are certainly possible if markets can absorb the output. The educational potential of Aquaponic systems is already being realized in hundreds of schools where students learn a wide range of subjects by constructing and operating Aquaponic systems. Regardless of scale or purpose, the culture of fish and plants through aquaponics is a gratifying endeavor that yields useful products—food.