FROG Water Care Experts Glossary of terms

The "heart" of the centrifugal pump. Rotating veins create the suction flow of the water into the pump. Pumps do more pushing than pulling.

The water entering the pump, the filter or other equipment of space. Water going into the pump is called influent, while water leaving the pump is called effluent.

A fitting in the pool or spa on the water return line from the equipment that water returns to the pool. Usually the last thing on the return line.

A water sanitation device that uses electricity to generate copper and/or silver ions, which are dispersed in the water. It works by passing a low-voltage DC current through a set of metallic electrodes placed in line with the circulation equipment. The copper is an algaecide, while the silver is a bactericide. It does not remove swimmer waste.

Iron in water can cause the water to be brown or green colored. This can be controlled by the addition of a sequestering or chelating agent. Water can be tested with an iron test kit.