How to get rid of rust residue in PVC plumbing pipe?
I have done this using bleach added at the filter housing, after the softener. Problem is, you need to close the toilet supply valves, washing machine supply hose connections and figure out if you really want to fill your water heater with this solution. I added bleach until I got the bleach smell at the last fixture from the supply pipe. Then let it sit 10 minutes and flushed with clear water. This is not a good method if you have a septic tank. I had a set-up where I flushed out through the outside faucets.
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