Replacement Filters for the Pentair GRO-2550 Reverse Osmosis System
Pentair · 4-Stage High-Recovery RO
Replacement Filters for the Pentair GRO-2550 Reverse Osmosis System
Every filter your GRO-2550 needs — stage by stage — led by the IPW kit with a 1:1 high-recovery membrane.
Also sold as: Pentair GRO-2550 · GRO-2550 50 GPD · Pentair 4-stage GRO RO
✓ Complete change — 3 cartridges + 1:1 membrane
Pentair GRO-2550 compatible filter kit — 50 GPD
$107.99
Sediment + carbon block + inline GAC with 3/8" quick-connects + PureT EZRO-50 1:1 encapsulated membrane.
🛒 Add the kit to cartPrefer the genuine membrane? Get the kit with Pentair GRO-50EN (4002574) — $137.99
Filters by stage
Buy a kit above, or replace stages individually below.
1
Sediment pre-filter
5µm polypropylene · standard 10" × 2.5"
IPW 5M-SED — 5µm sediment — $3.50
Name-brand alternative: Pentek P5 — $10.83
2
Carbon block pre-filter
5µm coconut carbon block · standard 10" × 2.5"
3
RO membrane — 1:1 high recovery
50 GPD encapsulated GRO element with check valve · do not substitute a standard 1812 TFC
Genuine Pentair OEM: Pentair 4002574 (GRO-50EN) — $136.23
4
Inline post-carbon
10" × 2" coconut GAC · 3/8" quick-connect
IL-10W-C-EZ38 — inline GAC, 3/8" QC — $12.99
When to replace
🪣 Sediment & carbon: every 6–12 months🥤 Inline post-filter: every 12 months or 2,500 gal💧 GRO membrane: every 2–3 years
Fits the Pentair GRO-2550 with 10" × 2.5" housings and a 3/8" QC post-filter — not sure? call (714) 541-6600
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.
Pentair GRO-2550 filter FAQ
What filters does the Pentair GRO-2550 use?
A 5 micron sediment and a carbon block pre-filter (standard 10" × 2.5"), a 50 GPD encapsulated 1:1 GRO membrane (Pentair 4002574 / GRO-50EN) and a 10" inline GAC post-filter with 3/8" quick-connects. Our GRO-2550 kit has all four.
Can I use a standard 1812 membrane in the GRO-2550?
No. The GRO-2550 is a high-recovery system that sends about 1 gallon to drain per gallon made. A standard 1812 membrane will not hold that ratio. Use the PureT EZRO-50 or the genuine Pentair 4002574.
Is the GRO-2550 the same as the Pentek RO-2550?
No. They share the same size pre-filters, but the GRO-2550 uses an encapsulated GRO membrane and a 3/8" quick-connect post-filter, while the RO-2550 uses a standard membrane and a ¼" threaded post-filter. See our Pentek RO-2550 page.
My old membrane says 4004424. Will these fit?
4004424 is the GRO-50EN version with the drain flow control built in. Call (714) 541-6600 before you order so we can match the right element.
All replacement filters by system · Pentair RO replacement filters & membranes · Franklin Electric / Pentair GRO-50-5 · Universal 4-stage RO
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.
