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Apec Water RO-PERM

Reverse osmosis system

Ultimate RO-PERM 4-Stage Pumped RO System Compatible Replacement Filters

The RO-PERM is built for low pressure water filtration situations. This unit comes equipped with a permeate pump to boost pressure out of your faucet and to cut down on waste water. Find your compatible replacement filters, parts and manuals below.

See the replacement schedule

Compatible parts

Everything that fits the Apec Water RO-PERM

Ready Water RW-SED2510050 5-micron sediment filter, direct replacement for 93023 and PX05-9 7/8
Top Seller
Ready Water
Ready Water RW-SED2510050 Sediment Filter 5 Micron 2.5" x 10"
(89)
$8.99
Meets FDA requirements for food and beverage contact
Omnipure OMB934-5m 5-micron carbon block filter for standard 10-inch water filter housings
Omnipure
Omnipure OMB934-5m Carbon Block Filter 5 Micron 2.5" x 10"
(83)
$14.99
Reduces chlorine, taste and odor
NSF Certified performance
USA made compression molded
2.5" Drop-in carbon block element
AXEON TF-1812-25 25 GPD thin-film composite reverse osmosis membrane, part 200357
Pentair
AXEON 200360 TFC-1812-75 Reverse Osmosis Membrane 75 GPD
(9)
$48.99
Thin Film Composite (TFC)
NSF 58 Certified
Omnipure K2533 inline GAC T33 carbon filter, 2 x 10 inch
Omnipure
Omnipure K2533 GAC T33 Granular Carbon Inline Filter 2" x 10"
(56)
$15.99
Reduces chlorine, taste and odor
NSF 42 Certified
Select an option
PAE RO-132 TKE-3200W 4.4-gallon reverse osmosis water storage pressure tank
Top Seller
PAE
RO-132 RO Water Storage Pressure Tank 4.4 Gallon
(88)
$59.99
NSF Certified
Reverse osmosis maintenance kit with filter wrench, sanitizer packet, O-rings and silicone lubricant
ESP Water
RO Maintenance and Sanitizing Kit for Most Standard RO Systems
(26)
$18.94

Replacement filter info

Your replacement schedule

Each stage of the Apec Water RO-PERM, the exact part that fits it, and when to change it.

  1. Stage 1: Sediment filter

    Part RW-SED2510050, Ready Water RW-SED2510050 Sediment Filter 5 Micron 2.5" x 10" $8.99

    Every 6–12 months

  2. Stages 2 to 3: Carbon block filter × 2

    Part OMB934-5m, Omnipure OMB934-5m Carbon Block Filter 5 Micron 2.5" x 10" $14.99 each

    Every 6–12 months

  3. Stage 4: RO membrane

    Part 200360, AXEON 200360 TFC-1812-75 Reverse Osmosis Membrane 75 GPD $48.99

    Every 2 years

  4. Stage 5: Post carbon filter

    Part K2533-JJ, Omnipure K2533 GAC T33 Granular Carbon Inline Filter 2" x 10" $15.99

    Every 6–12 months

Manuals & instructions

Manuals and guides

FAQ

Ultima RO Frequently Asked Questions

How much do Ulitma water filters cost?

Ultima Reverse Osmosis propriety water filters can be expensive. But we offer high-quality compatible filters, RO membranes, and cartridges, that work well with Ultima RO systems and can save you money. Basically, the filters cost much less, but provide that same clean, great-tasting drinking water you'd expect. By installing Ultima-compatible reverse osmosis filter replacements and taking care of routine system maintenance yourself, you can save quite a bit of money.

How do I order replacement filters for my Ultima Reverse Osmosis water filtration system?

Begin by selecting the image of your Ultima RO system displayed on this page https://ispwaterproducts.com/collections/ultima-reverse-osmosis. This will allow you to add the appropriate filters to your shopping cart. For convenience, consider opting for a "filter kit" which includes all the necessary filters, though it might not be available for every Ultima model. Remember, the RO membrane typically requires replacement every two years, while sediment and carbon filters need changing every 6-12 months based on your water consumption and its quality.

What contaminants will these Ultima-compatible filters remove?

Ultima-compatible reverse osmosis filters and membrane can remove common pollutants from water including pesticides, sulfates, fluoride, nitrates, lead, pharmaceuticals, arsenic and more. The RO system's carbon filter will also remove chloramines and chlorine.

Learn more about what contaminants can be removed with reverse osmosis filtration.

How often should I replace filters in my Ultima Reverse Osmosis system?
In Ultima RO systems, replace sediment and carbon pre-filters every 6–12 months, and the RO membrane every 2 years for reliable performance and water quality. Replacing on schedule helps maintain the benefits of RO drinking water — learn more on the RO advantages page. Explore replacement options in the Ultima RO Replacement Filters collection.
What filter kits are compatible with Ultima RO systems?
ESP Water carries multiple Ultima RO filter kits including the Ultima Green RO 4-Stage, Ultima Green RO 5-Stage, Ultima RO 5 QC System, Ultima VI RO System, and Ultima VII RO System. Match your model to the correct kit for optimal performance.
How do I know which Ultima RO replacement filters I need?
Start by identifying your system model (4-stage, 5-stage, or advanced Ultima VI/VII). Then use the ESP Water Replacement Filter Finder tool or browse the Ultima RO filters & parts collection to find the exact match.
What are the signs Ultima RO filters need replacing?
Common signs include slow water flow, poor taste or odor, cloudy water, or higher TDS readings. Slow flow can be due to clogged filters — see causes in the Why RO Water Flow Is Slow page. Replace any outdated filters as soon as you notice these symptoms using parts from the Ultima RO Replacement Filters collection.
Can I install Ultima RO filter replacements myself?
Yes — Ultima RO filters are designed for straightforward DIY replacement. Turn off feed water, depressurize the system, and swap cartridges following your system manual. For general instructions, see the RO Filter Replacement Guide and then choose the correct kit from the Ultima RO filters collection.
How do Ultima RO replacement filters improve water quality?
Fresh sediment filters trap dirt and particles, carbon blocks reduce chlorine and tastes/odors, and the RO membrane removes dissolved solids and contaminants — preserving the key benefits of reverse osmosis water described on the RO advantages page. Replacing filters on schedule ensures consistent water purity.
Are all Ultima RO replacement filters the same size?
Not always. Ultima systems use different stage configurations and filter sizes depending on the model (e.g., 4-stage vs. 5-stage vs. Ultima VI/VII). Always verify your system model and select the correct replacement kit from the Ultima RO Replacement Filters collection or via the Replacement Filter Finder tool.

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