
Overall the filters seem good. I am very happy with my reverse osmosis device. I noticed that the unit backwashed almost constantly and realized it needed new filters. I have approximated the service life of the original filters to 8 months. I was amazed how black the original filters were when I replaced them with new ones. I've attached a photo of one of the old ones next to one of the new ones. The first and second stage filters were all black with iron.

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