The Flow Indicator is an excellent diagnostic tool for chemical feed pumps.

Rhythmic rising and falling of the ball indicates positive flow.

Air bubbles indicate chemical has exhausted.

Stationary ball indicates no flow.

Possible problems could be:

lost prime

stopped motor

plugged injection fitting

faulty tube or diaphragm

plugged or dirty footvalve filter

chemical has been exhausted for a lengthy period of time

Blue-White recommends using:

Glass bobbin for Chlorines and Acids