Guides

Choose, test, install, maintain. Every guide ships with a free one-page PDF. We don't cure disease; we filter water.

How to Choose an RO Water Filter

Four things matter. Everything else is marketing.

A $15 pen that tells you when your filters are done. Here's how to read it.

15 minutes, no plumber, one rookie mistake to avoid.

We sell a system that uses universal filters. Here's the honest version anyway.

Forget the calendar. Learn the signals.

Taste is a diagnostic tool. Here's the decoder.

If you can use a wrench, you can do this. No plumber required.

One $12 gauge answers this question definitively.

Skip this and your first glass looks like ink. Here's the 20-minute fix.

Yes, RO wastes water. Here's how much, why, and what actually helps.

The sticker price is the lie. Proprietary cartridges $80–150/yr vs universal 10" $30–60/yr — the real math, stage by stage.

10" × 2.5": the universal cartridge standard. What fits, what doesn't, and how to check in 30 seconds.

Three questions that reveal whether a water filter owns you. Red flags, green flags, and the honest case for lock-in.