Just keep an eye on it. I just changed my pre filter and one of my carbon filters
and both DI canisters on Jan 16th and today I am reading 1 ppp out from first DI canister. I worked it out and would say 170 to 200 gal of water at 5 ppm went threw the resin. I don't know but it seems a little low to me for life span at 5 ppm input.
Skim
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