So who is this cartridge really for? Not much if any info about it on your website. With your 4 stage Ro/Di system my nitrate with a API FW No3 test kit are 0ppm out the unit and my final TDS is 0ppm. Before the unit I'm No3 20-30ppm and 35 TDS out the tap.
Twist-In Nitrate Removal Cartridge
Description Item 330448 Download the Twist-In Cartridge Spec Sheets HERE Specifications Video
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