Replacement Filters for the Watts W-525 (5-Stage) Reverse Osmosis System
Watts · 5-Stage Reverse Osmosis
Replacement Filters for the Watts W-525 (5-Stage) 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: Watts W-525 · W-525 · Watts 5 stage RO
✓ Best value — replace everything at once
W-525 IPW set + 3/8" QC inline — best value
$47.99
5µm sediment + 2 coconut carbon blocks + 50 GPD membrane + 10" inline GAC with 3/8" quick-connects. Fits the Watts W-525.
🛒 Add the complete set to cartFilters by stage
Buy the whole set above, or replace stages individually below.
2
Carbon block / GAC
5µm coconut carbon block · 10" × 2.5"
3
Carbon block / GAC (2nd)
5µm coconut carbon block · 10" × 2.5"
4
RO membrane
50 GPD thin-film composite · standard 1812 size
IPW TW-1812-50 — 50 GPD membrane — $32.99
5
Inline post-carbon polish
10" × 2" coconut GAC · 3/8" quick-connect (replaces Watts W560033)
ICF-10Q38 — inline GAC, 3/8" QC — $12.99
When to replace
🪣 Sediment & carbon: every 6–12 months🥤 Inline post-filter: every 12 months💧 RO membrane: every 2–3 years
✓ Guaranteed to fit your Watts W-525 5-stage RO.
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Watts W-525 filter FAQ
What filters does the Watts W-525 use?
Five stages: a 10" × 2.5" 5 micron sediment filter, two 10" × 2.5" 5 micron carbon blocks, a 50 GPD 1812-size RO membrane and a 10" × 2" inline GAC post-filter with 3/8" quick-connects. The W-525 set has all five.
Does the W-525 inline filter use 1/4" or 3/8" fittings?
The W-525 post-filter has 3/8" quick-connect ends (it replaces Watts W560033). Order the 3/8" QC version, like the ICF-10Q38. If your tubing is 1/4", call (714) 541-6600 and we will match it.
How often should I change the W-525 filters?
Replace the sediment and carbon filters every 6 to 12 months and the inline post-filter every 12 months. The membrane usually lasts 2 to 3 years. Change sooner if flow drops or the taste changes.
Will a standard 50 GPD membrane fit the W-525?
Yes. The W-525 takes a standard 1812-size 50 GPD membrane, like the IPW TW-1812-50.
All replacement filters by system · Watts RO & OneFlow replacement filters · Watts W-415 (4-stage) · Watts RO-TFM-5SV / WP5-50
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.
