I explained how big my system was awhile back.
1 20” prefilter, 2 x 20bb carbon, 1 x 20bb chlorplus, 1 chloraplus 10”, 2x 10” matrix carbon blocks, 2 x 90gpd spectrapure membrane in series, then to 1 x 20bb Di and 1x 10” di canister .
Last changed lasted a year before tds creeping up.
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