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My Water Club support
4-Stage Countertop RO (CRO4T)
Replacement filters, the filter change guide and the manual for your system.
This page is for these models
Bought on Amazon
MWC-CRO4T-100-FG
Bought on MyWaterClub.com
CRO-4T-100-… or CRO-4T-150-…
The number 100 or 150 is your RO membrane size in gallons per day (GPD). The letters at the end show the faucet connection type. You can find the model number on your order confirmation.
Replacement filters
Your system uses two sets, on a simple schedule. Filter life varies with your water quality and how much water you use.
Every 12 months
Annual filter set
3 filters: sediment, T28 carbon and T33 post-carbon. The RO membrane is not included.
Every 24 months
Complete set with RO membrane
The same 3 filters plus a new RO membrane. Choose the membrane size your system uses now, 100 or 150 GPD. It is the number in your model number.
Which set do I need this time?
Year 1: annual filter set. Year 2: complete set with membrane. Then repeat. The date you wrote on the sticker under your unit shows when the filters were last changed.
How to replace the filters
The guide shows all 18 steps with photos. Plan for 25 to 35 minutes.
- You need the new filter set, pliers and paper towels.
- A collet tool makes the tubing easier to release. It is recommended but not required.
- Take two photos of your system, front and back, before you start.
- After the change, check for leaks and flush the system for 20 to 30 minutes before drinking the water.
Open the filter change guide (PDF)
Manual and setup
The manual covers first use, connecting to your faucet, leak checks, TDS and pH testing, and the warranty.
- Use cold water only.
- Flush the system for 20 to 30 minutes before first use.
- The system makes water slowly, so collect it in advance.
Need help?
We answer questions about setup, leaks, adapters and filter changes.
If you bought on Amazon, you can also reach us through the Amazon Message Center.