-Been There Done That Dept-
Remove filter
Add three drops of water purifier IODINE
Assemble
Run an few quarts of fresh tank water through the filter before re-using. Iodine kills moss, bacteria, amoeba, protozoa, and keeps working for years. Follow directions on label for dosage. If you won't hurt you if you purify water in a drinking glass it won't hurt you in a filter, especially one that gets a flushing.
Quicksilver, is stored with 1.15 pints of purified iodine in the filled water tank, throughout the system including pump lines and faucets. But when I go to use it, it sure gets one heck of a flushing. Iodine is far and away easier on pumps and seals than chlorine bleach, plus it is far more potent and long lasting. I scribbled a reminder YODO/IODINE on post-it-notes for the sink and shower, especially to remind the kids.