Liquid chemical feeders are helpful for many applications, but erosion feeders present a simpler alternative for systems in need of regular chlorine dosing.

Instead of pumping chemicals through a tube, erosion feeders are installed inline after the pump and filter. Thus, water flows through them to gradually erode dry chlorine tablets, or granular chlorine, which sits in a vertical chamber.

The main advantage of an erosion feeder over manually adding chlorine is simplicity: Once the stack of tablets or the granular chlorine is added, chlorine will flow into the pool until the feeder’s contents are depleted.

Another type of dry chemical feeder soaks the chemical rather than erodes it. This makes it more difficult to ensure that the chlorine enters the water at a constant rate.

“You tend to get peaks and valleys in your output when the whole container is wet,” says Lynn Nord, marketing manager at King Technology Inc. in Hopkins, Minn. “When the whole container is full of chlorine, it releases chlorine faster than when there’s only, say, two pounds of chlorine in there.”

This is not the case with erosion design feeders that hold most of the chlorine up in a dry area, away from the water, while only exposing the lower third or fourth of the chlorine to the flow. Certain feeders even include adjustment levers, which increase the velocity of the water over the dry chlorine to adjust the rate of dissolution.

For customers on a budget who still want some of the benefits of automation, erosion feeders may provide a suitable solution.