Pentair cartridge filter rust


New member
Sep 19, 2021
La Quinta, CA
I've got the same problem - removed the ring and have another one on order from Pentair - I would imagine the same rust problem will occur - thinking of leaving it off since there's a metal band on the outside of the filter - any thoughts would be appreciated!


TFP Expert
Mar 2, 2011
They use good quality stainless steel but the manufacturing process can damage the molecular structure of the steel and make it susceptible to corrosion.

They use heat and pressure to bend the steel and weld it into a circle.

Extreme care needs to be used to avoid damaging the molecular structure of the steel when the product is being manufactured.

It is a quality control issue that needs to be addressed at the manufacturing stage.

The band is necessary for the structural integrity of the filter.

The band should not be left out as the filter can warp or deform in a way that creates a risk of the top coming loose or the filter can possibly crack.