Water Doctor

Water Doctor 4-Stage Undersink RO System

$799.99 CAD $899.99 CAD
11% off
SKU: ROS4A
Enjoy clean and safe drinking water with the 4-Stage Reverse Osmosis System, a complete set that includes filters, storage tank, faucet, and professional installation. Complete Filtration Set – Comes with...

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Water Doctor 4-Stage Undersink RO System
$799.99 CAD

Before you choose a drinking-water system

Compare flow rate, storage style, and filter maintenance with Water Doctor if you are not fully sure this is the right RO system for your household.

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If you are still diagnosing the problem, use one of these tools before you commit to checkout.

Water Diagnosis Check Water Hardness Rule out a whole-home hardness problem before solving only the drinking-water tap. Guided Selection Help Me Choose Use the guided path to compare RO, whole-home filtration, and hardness-led next steps.
Estimated delivery: May 24 - May 28
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Enjoy clean and safe drinking water with the 4-Stage Reverse Osmosis System, a complete set that includes filters, storage tank, faucet, and professional installation.

  • Complete Filtration Set – Comes with 4 cartridges, faucet, and storage tank for a full home solution.

  • 4 Stages of Filtration –

    1. PP Sediment Filter – Removes rust, sand, and large particles.

    2. GAC Carbon Filter – Adsorbs chlorine, odor, and organic chemicals.

    3. CTO Carbon Block – Further removes residual chlorine, heavy metals, and improves taste.

    4. RO Membrane (0.0001 μm) – Filters dissolved solids, bacteria, heavy metals, and other harmful contaminants.

  • Faucet Included – Dedicated lead-free faucet for pure water dispensing.

  • Storage Tank – Ensures a steady supply of clean water when you need it.

  • Professional Installation Service – Hassle-free setup for long-term reliability.

  • Safe & Reliable – High-purity filtration system that guarantees fresh, great-tasting water every day.

Perfect for families looking for an affordable, effective, and easy-to-use RO water system.
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  • Free Assessment

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  • Installation Planning

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  • Shipping and Support

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  • Replacement Ready

    Keep maintenance, filters, and UV lamp replacements simple over time.

    Buy with more confidence

    Water Doctor is strongest when product, installation, and maintenance are treated as one system.

    • Confirm the Right Fit

      Match this product to your water problem, household size, and plumbing setup before checkout.

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    • Plan Installation

      Check access, service area, and installation timing so there are no surprises after purchase.

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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

    Need help confirming fit, installation, or maintenance?

    Water Doctor can help you verify whether this product matches your water problem, installation setup, and replacement schedule before checkout.
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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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