Pleatco PMAX50P4 = Unicel 5CH-35 = Filbur FC-0300
50 sq ft hot tub filter, 5-3/4" diameter × 8" long. Top: Handle · Bottom: 1-1/2" MPT. Pleatco application: Maax Spas of Canada.
Interchangeable cartridges
- Unicel 5CH-35 confirmed by: Pleatco p.47 (Unicel to Pleatco cross reference) Unicel p.11 (Cartridges by series (dimensional listing))
- Filbur FC-0300 confirmed by: Pleatco p.48 (Filbur to Pleatco cross reference) Filbur p.34 (Reverse cross reference (Unicel to Filbur)) Filbur p.10 (Dimensional cartridge listing)
Check before you order
- Unicel 5CH-35 rates it 35 sq ft (vs 50 sq ft); filter area ratings differ by maker.
- Filbur FC-0300 rates it 35 sq ft (vs 50 sq ft); filter area ratings differ by maker.
Published dimensions, side by side
Each manufacturer measures a little differently. Compare these with your old cartridge.
| As published by | Pleatco PMAX50P4 source | Unicel 5CH-35 source | Filbur FC-0300 source |
|---|---|---|---|
| Outside diameter | 5-3/4" | 5-5/8" | 5-5/8" |
| Length | 8" | 8" | 8" |
| Top end | Handle | / semi-circular handle | Handle |
| Bottom end | 1-1/2" MPT | / 1-1/2" male thread/MPT | 1-1/2" MPT |
| Filter area | 50 sq ft | 35 sq ft | 35 sq ft |
| Pleats | not listed | 203 | not listed |
| Media weight | 3 oz/yd² | 3 oz/yd² | not listed |
Where to buy
Search any retailer for 5CH-35 or PMAX50P4 or FC-0300. These are the same cartridge under different brand names.
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OEM part numbers this cartridge replaces
As printed in the cited aftermarket catalogs. Match the number on your old cartridge or in your spa manual exactly.
| OEM number | Listed in |
|---|---|
104309 | Unicel p.44: OEM cross reference: Maax Spas of AZ |
Hot tub brands that use it
From the spa-manufacturer cross reference in the Unicel 2026 Replacement Guide. A brand may use several sizes, so check your measurements.
- Elite Spas by Maax Unicel p.34
- Maax Spas of AZ (models: Elite Spas; OEM 104309) Unicel p.44
FAQ
What is the Unicel equivalent of Pleatco PMAX50P4?
The catalogs cross-reference Pleatco PMAX50P4 to Unicel 5CH-35.
What is the Filbur equivalent of Pleatco PMAX50P4?
The catalogs list Filbur FC-0300.
What size is the PMAX50P4 filter?
Pleatco lists PMAX50P4 as 5-3/4" outside diameter by 8" long, top: Handle, bottom: 1-1/2" MPT, 50 sq ft.
Which OEM part numbers does it replace?
Listed OEM numbers: 104309.
Sources: Filbur Product Catalog and Reference Guide (2024) · Filbur Product Catalog and Reference Guide (2024) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Pleatco 2023 Catalog & Cross Reference Guide (Pentair) · Unicel 2026 Replacement Guide. Last checked 2026-10-21.