System maintenance
Five Matching Filtration Stages
Includes sediment, T28 carbon, the selected RO membrane, T33 post-carbon, and 3-in-1 alkaline cartridges.
5-Stage Alkaline Countertop RO Replacement Filter Kit — Sediment, T28, 75/150 GPD Membrane, T33, 3-in-1 Alkaline, Wrench & 8 Fittings — SKU 4FILTERATM
Price range: $77.00 through $129.00
5 Filter Set for 5-stage Alkaline Countertop RO Systems, including Sediment, T28, 75 or 150 GPD RO membrane, T33 & 3-in-1 Alkaline inline filter cartridges, SKU #4FILTERATM
- Description
- Additional information
- Reviews (1)
Description
Complete 5-stage alkaline countertop RO service kit
Five replacement filters with RO membrane, 3-in-1 alkaline post-filter, wrench, and eight fittings
This complete maintenance set is designed for compatible 5-stage alkaline portable and countertop reverse-osmosis systems using inline quick-connect filters. It replaces the sediment, T28 carbon, RO membrane, T33 post-carbon, and 3-in-1 alkaline stages and includes service accessories for a more complete filter change.
5 filtersComplete five-stage alkaline set
75 or 150 GPDSelect the matching RO membrane
8 fittingsReplacement connections included
1 wrenchMembrane-housing service tool
Complete replacement package
Refresh all five filtration stages at the same time
The set replaces every water-treatment cartridge in a compatible 5-stage alkaline countertop RO system. Changing the full set helps restore sediment protection, chlorine pretreatment, membrane performance, taste polishing, and final mineral or pH adjustment.
Service accessories
Wrench + Eight Replacement Fittings
Includes one compatible membrane-housing wrench and eight replacement fittings for renewing selected cartridge and membrane-housing connections.
Five replacement stages
Protection, membrane separation, carbon polishing, and alkaline mineral treatment
1
5-Micron Sediment Filter
Helps capture rust, sand, dirt, and suspended particles before they reach the carbon filter and RO membrane.
2
T28 Coconut Carbon Filter
Helps reduce chlorine, taste, odor, and selected organic compounds while helping protect the membrane.
3
RO Membrane
Choose the output that matches the current system configuration: 75 GPD or 150 GPD.
4
T33 Coconut Carbon Filter
Provides final taste and odor polishing after reverse osmosis.
5
3-in-1 Alkaline Post-Filter
Contains alkaline, ORP-related, tourmaline, and calcite media intended to add selected minerals and may increase the pH of acidic RO water.
Package contents
Filters and service parts included
- ✓1 × 5-micron inline sediment filter
- ✓1 × T28 coconut-shell activated carbon prefilter
- ✓1 × selected 75 or 150 GPD RO membrane
- ✓1 × T33 coconut-shell activated carbon post-filter
- ✓1 × 3-in-1 alkaline post-filter
- ✓1 × membrane-housing service wrench
- ✓8 × replacement fittings
Key benefits
A complete alkaline RO service kit with replacement hardware
Complete Five-Stage Set
Replaces every filtration stage in a compatible 5-stage alkaline countertop RO system.
New RO Membrane Included
Select the same membrane rating used with the current flow restrictor.
Alkaline Mineral Post-Filter
The final cartridge may add selected minerals and increase the pH of acidic RO water.
Eight Replacement Fittings
Refreshes selected filter and membrane-housing connections during service.
Service Wrench Included
Helps open the compatible membrane housing during membrane replacement.
Inline Quick-Connect Format
Designed for compatible classic countertop systems using standard 1/4″ tubing connections.
Specifications
Verified filter details
| Product type | Complete 5-stage alkaline countertop RO replacement-filter and service kit |
|---|---|
| Compatible system type | Selected 5-stage alkaline portable and countertop RO systems using inline quick-connect cartridges |
| Sediment filter | 5 micron, approximately 10″ × 2″, 1/4″ female ports |
| Carbon prefilter | T28 coconut-shell activated carbon, approximately 10″ × 2″, 1/4″ female ports |
| RO membrane options | 75 GPD or 150 GPD on the MyAquaFilter listing |
| Post-carbon filter | T33 acid-washed coconut-shell carbon, approximately 10″ × 2″, 1/4″ female ports |
| Alkaline post-filter | 3-in-1 alkaline cartridge, approximately 10″ × 2″, 1/4″ female ports |
| Listed alkaline media | Alkaline, ORP-related, tourmaline, and calcite media |
| Replacement fittings | 8 pieces included |
| Service wrench | 1 included |
| Filter quantity | 5 cartridges total |
| Listed package dimensions | 12 × 10 × 6 in |
| Listed package weight | 84 oz / 5.25 lb |
| SKU | 4FILTERATM |
| Parent SKU listed | 4FILTERAT1 |
Typical service life
- ✓Sediment filter: replace based on flow, discoloration, sediment load, or the system schedule
- ✓T28 and T33 carbon filters: approximately 8–12 months or up to the listed capacity, depending on water quality and usage
- ✓3-in-1 alkaline filter: approximately 8–12 months or when taste, pH, or mineral performance changes
- ✓RO membrane: approximately 2 years, depending on source water, pressure, prefilter maintenance, and measured rejection
Compatibility checklist
Confirm the existing system before ordering
✓
Five-stage alkaline configuration
The system should use sediment, T28 carbon, RO membrane, T33 carbon, and 3-in-1 alkaline filters in this sequence.
The system should use sediment, T28 carbon, RO membrane, T33 carbon, and 3-in-1 alkaline filters in this sequence.
✓
Inline 1/4″ tubing connections
Confirm that the existing filters use compatible 1/4″ tubing and removable fittings.
Confirm that the existing filters use compatible 1/4″ tubing and removable fittings.
✓
Matching membrane output
Select the same 75 or 150 GPD membrane rating used with the current flow restrictor.
Select the same 75 or 150 GPD membrane rating used with the current flow restrictor.
✓
Compatible membrane housing
The included wrench and membrane must match the existing classic countertop membrane housing.
The included wrench and membrane must match the existing classic countertop membrane housing.
Replacement guidance
Plan approximately 30–40 minutes for a complete filter change
1
Shut Off and Depressurize
Disconnect the system from the faucet and allow pressure to dissipate before removing tubing or fittings.
2
Record the Tube Routing
Photograph and label each tube before disconnecting the old filters.
3
Replace One Stage at a Time
Match each flow arrow and stage position, then install the supplied fittings where required.
4
Flush and Check for Leaks
Pressurize slowly, inspect every fitting, and flush all new filters before using the water.
Before purchase
Good to know
!
Confirm the membrane rating
A membrane with the wrong GPD rating may not match the installed flow restrictor or expected production rate.
A membrane with the wrong GPD rating may not match the installed flow restrictor or expected production rate.
!
Alkaline results vary
Final pH and mineral release depend on source-water chemistry, flow, contact time, and cartridge condition.
Final pH and mineral release depend on source-water chemistry, flow, contact time, and cartridge condition.
!
ORP is not guaranteed
The old listing gives fixed ORP values, but actual readings vary and require measurement under controlled conditions.
The old listing gives fixed ORP values, but actual readings vary and require measurement under controlled conditions.
!
Flush before use
New carbon, membrane, and mineral media require thorough flushing before taste, TDS, and pH readings stabilize.
New carbon, membrane, and mineral media require thorough flushing before taste, TDS, and pH readings stabilize.
!
Inspect tubing ends
Cut damaged or deeply scored tubing ends square before inserting them into replacement fittings.
Cut damaged or deeply scored tubing ends square before inserting them into replacement fittings.
!
Photo must show all included parts
The updated product image should display five filters, one wrench, and all eight replacement fittings.
The updated product image should display five filters, one wrench, and all eight replacement fittings.
This product includes five replacement filters, one membrane-housing wrench, and eight replacement fittings. It does not include a complete preassembled frame, membrane housing, countertop stand, faucet adapter, tubing set, clips, or flow restrictor unless explicitly selected or stated elsewhere on the product page.
Not sure whether this set matches your alkaline countertop RO system?
Send the system model, membrane GPD rating, filter labels, tubing size, and clear photos of the current assembly before ordering.
Send the system model, membrane GPD rating, filter labels, tubing size, and clear photos of the current assembly before ordering.
Additional information
| Weight | 84 oz |
|---|---|
| Dimensions | 12 × 10 × 6 in |
| Membrane | 150 Gallons per day, 75 Gallons per day |
| Choose | Assembly, Filter Set, Filter Set with new Quick Connect Fitting |
1 review for 5-Stage Alkaline Countertop RO Replacement Filter Kit — Sediment, T28, 75/150 GPD Membrane, T33, 3-in-1 Alkaline, Wrench & 8 Fittings — SKU 4FILTERATM
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