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Water Doctor

Water Doctor ROS4B Replacement Filter Cartridges - PP/CTO/T33/RO

$49.99 CAD
SKU: PP-10F
Keep your water clean and your RO system running strong.This complete replacement filter set is specifically designed for the Water Doctor ROS4B 4-Stage Reverse Osmosis System. Each cartridge plays a...

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Model: PP
Water Doctor ROS4B Replacement Filter Cartridges - PP/CTO/T33/RO
$49.99 CAD
PP

Before you reorder

Match the cartridge, lamp, or filter stage to your existing system before checkout so you do not end up with the wrong replacement part.

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Water Diagnosis Check Water Hardness If you are actually solving a new water problem, confirm the diagnosis before reordering parts. Guided Selection Help Me Choose Use the guided path if you are not sure a replacement purchase is the right next move.
Estimated delivery: Apr 16 - Apr 20
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Keep your water clean and your RO system running strong.
This complete replacement filter set is specifically designed for the Water Doctor ROS4B 4-Stage Reverse Osmosis System. Each cartridge plays a vital role in delivering fresh, purified drinking water to your home.

Included Filters:

  • PP Sediment Filter
    Removes rust, sand, dirt, and other large particles
    ➤ Recommended replacement: every 6 months
  • CTO Carbon Block Filter
    Removes chlorine, odors, and improves taste
    ➤ Recommended replacement: every 6–12 months
  • T33 Post Carbon Filter
    Polishes and enhances water flavor before it reaches your glass
    ➤ Recommended replacement: every 12 months
  • RO Membrane Cartridge (TFC, 0.0001 μm precision)
    Filters out bacteria, viruses, heavy metals, and dissolved solids
    ➤ Recommended replacement: every 2–3 years

Quick Twist Design – Easy DIY Installation
Each cartridge is built for quick twist replacement, requiring no tools or plumbing skills. Replace your filters in seconds!

Pure Water Starts with Clean Filters
Ensure optimal performance and maximum protection for your family by replacing filters on schedule.
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    • Think About Maintenance

      Replacement filters, UV lamps, and long-term care should be part of the buying decision from day one.

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    Before you order

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    After purchase support

    Keep performance high with the right replacement and service plan.

    Water treatment performance depends on timely maintenance. Save your model details, set replacement reminders, and use Water Doctor support when unsure about cartridges, UV lamps, or service intervals.
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