Replacement Filters for the Franklin Electric / Pentair Green RO GRO-50-5 (5-Stage) Reverse Osmosis System
Franklin Electric / Pentair · Green RO · 5-Stage
Replacement Filters for the Franklin Electric / Pentair Green RO GRO-50-5 (5-Stage, 50 GPD) Reverse Osmosis System
Every filter your system needs — stage by stage — led by the IPW house-brand set that costs less than the OEM parts.
Also sold as: GRO-50-5 · GRO-50-5-WHT-BR · Green RO 5STG 50GPD · Ultima Green RO 5-Stage
✓ Best value — replace everything at once
GRO-50-5 cartridge set — sediment + 2 carbon blocks + inline
$26.99
Guaranteed to fit your Green RO GRO-50-5. Membrane versions available on the product page.
🛒 Add the complete set to cart
One thing to check before you buy a membrane. The Green RO is a high-recovery system — its encapsulated element sends roughly 1 gallon to drain per gallon produced instead of the 4:1 a conventional RO wastes. Pentair makes the GRO-50EN in two versions: 4004424 with the drain flow control built in, and 4002574 without it. Check the label on your old element. If it says 4004424, call us at (714) 541-6600 before you swap. A standard 1812 TFC membrane will not hold the 1:1 ratio — use a GRO-style encapsulated element only (stage 4 below).
Filters by stage
Buy the whole set above, or replace stages individually below.
1
Sediment pre-filter
5µm, 10×2.5 — replaces OEM 93023
IPW 5M-SED-10×2.5 — 5µm sediment — $3.50
Name-brand alternative: Pentek P5 — $10.83
2
Carbon block
5µm, 10×2.5 coconut carbon — replaces OEM OMB934-5M
Name-brand alternative: KX MatriKX 32-250-10 CTO — $12.08
3
Carbon block (2nd pass)
5µm, 10×2.5 — the GRO-50-5 runs two in series
Name-brand alternative: KX MatriKX 32-250-10 CTO — $12.08
4
RO membrane — 1:1 high recovery
50 GPD 1:1 encapsulated element with integral check valve, 2.5" × 16" — do not substitute a standard 1812 TFC
Genuine Pentair OEM: Pentair 4002574 (GRO-50EN) — $136.23
5
Inline post-carbon polish
2×10 GAC, ¼" FPT both ends — replaces OEM CL10ROT33-BB
Name-brand alternative: Omnipure CL10ROT33-B (exact OEM part) — $12.99
When to replace
🪣 Sediment & carbon: every 6–12 months💧 RO membrane: about every 2 years🔧 O-rings: inspect at every change
✓ Guaranteed to fit your Franklin Electric / Pentair Green RO GRO-50-5 / GRO-50-5-WHT-BR (5-Stage, 50 GPD).
Not sure this is your system? Use the Isopure Water Filter Finder → Match by system name, by the part number printed on your current filter, or by snapping a photo of the label.
Green RO GRO-50-5 filter FAQ
What filters does the Green RO GRO-50-5 use?
Five stages: a 10" × 2.5" 5 micron sediment filter, two 10" × 2.5" 5 micron carbon blocks (OEM OMB934-5M), a 50 GPD 1:1 encapsulated membrane (GRO-50EN) and a 10" × 2" inline GAC post-filter with ¼" female threads (OEM CL10ROT33-BB). Our GRO-50-5 set has all four cartridges, with membrane options.
How often should I change the GRO-50-5 filters?
Replace the sediment, carbon and inline filters every 6 to 12 months, and at least once a year. The membrane lasts about 2 years.
Can I use a regular RO membrane in the Green RO?
No. A standard 1812 membrane will not hold the 1:1 waste ratio. Use a GRO-style encapsulated element such as the Pentair GRO-50EN or PureT EZRO-50.
Which GRO-50EN membrane do I need?
Pentair sells it with built-in drain flow control (4004424) and without (4002574). Read the label on your old element. We stock the 4002574 and the PureT EZRO-50. If yours is a 4004424, call (714) 541-6600 first.
All replacement filters by system · Pentair RO replacement filters & membranes · PureT RO550-905 · APEC ROES-50
Compatibility reference only. Photos of complete systems shown on this page are provided to help you identify your unit and confirm that our filters fit. All brand names, model numbers, and product images are the property of their respective owners; Isopure Water (IPW Industries Inc.) is not affiliated with, sponsored by, or endorsed by these manufacturers. We sell compatible replacement filters and parts — not the branded systems pictured, unless a system is separately listed for sale on our store.
