
Hydronix makes excellent filters and these 1 micron filters are just what I needed. I use them as a pre- and post-filter for my water treatment system, which consists of an activated carbon filter and a water softener. The pre-filter catches almost all of the sulfur particles that precipitate out of the water pumped from the aeration tank. The post-filter catches carbon fines or loose particles from the water softener. The 20 inch filters are the way to go as I can't even detect any pressure drop across the pump. Highly recommended.

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