There was more on the page I listed:

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12.(OPTIONAL) If cartridge needs to be acid cleaned, take 2nd container and fill 1/2 with water.
(Do NOT acid clean because it *might* help!)
13.(OPTIONAL) Add 1/4 gallon of muriatic acid per 5 gallons of water. If removing metals, also add 1/2 pound of ascorbic acid. Mix.
14.(OPTIONAL) Place double rinsed cartridge in acid solution & cover.
15.(OPTIONAL) Wait at least 1 hour. Remove cartridge after no more than 4 hours.
16.(OPTIONAL) Rinse carefully and thorougly with water; allow to drain; rinse again.
17.(OPTIONAL) Store solution covered for re-use; renew with 1/8 gallon of muriatic and 1/4 lb of ascorbic acid.
18.(OPTIONAL) Before disposing of solution, neutralize with soda ash -- added SLOWLY! Add soda ash repeatedly till fizzing stops.
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19. Store cartridge in a secure location till ready to use. (Or leave in TSP soak)


See that line #19. I guess that is part of one of my answers.


The cartridges I'm using are the Unicel type ( http://www.amazon.com/exec/obidos/AS...ZK/scouscho-20 ) for my above ground pool. I'm told 2 of them should make it through the season alternating them between the TSP solution every 2 weeks. I just changed them out for the first time and this filter is so much better than the intex ones for this filter pump. I still had plenty of flow but went through this process anyways because I thought I needed to. I'm thinking I'll try to wait a month this time and see how dirty the brand new filter is compared to the first brand new one was when I took it out today after its first 2 weeks of life. I'd love to only have to swap them out every 3 months or so. that would be awesome.