jpa0741
New member
<a href=showthread.php?s=&postid=14380632#post14380632 target=_blank>Originally posted</a> by melev
The prefilters should be changed every six months like clockwork. The membrane should be good on average from 3 to 5 years, but that varies greatly due to water quality in each person's area.
The DI is changed when the resin is spent, so by testing the TDS before the DI and after, you can see how well the membrane is doing it job.
I checked just the ro and it was 15 tds. so I am guessing that it is still working fine.