Before you can select a pump that will fit your needs, you must know four things:
1) the total head or pressure against which it must operate,
2) the desired flowrate,
3) the suction lift, and
4) characteristics of the fluid.
Aquaculture operations imply that you will be pumping water,but you also need to know such things as the temperature range, the corrosiveness (is it salty water?), and how much and what kind of trash or debris such as sand, dirt, leaves, fish or twigs may be in the water. With this knowledge, you and your dealer can select the proper pump. The total head, suction lift and flow rate are dependent upon the piping system and the pump’s characteristics. The piping system and the pump interact to determine the operating point of the pump flow rate and pressure.
The pump cannot independently control these parameters. As the flow rate is increased the work to move each unit of water or total dynamic head the pump must produce increases. A pump will typically have reduced capacity as the pressure or head it is pumping against increases. The operating point of the system occurs when the two curves cross.
In order to obtain a pumping system that will meet your requirements, and meet them in an efficient manner, you must match the pump to the piping system and required flow rate. Manufacturers should be able to supply a pump curve which shows the performance of the pump and the allowable operating ranges. Do not plan to operate outside of this recommended range outside this may damage the pump. Your dealer may also be able to help you analyze or plan your piping system. Information on piping systems is also available in the SRAC Publication No. 373, Piping Systems.