How to Choose the Right Unicel Filter Cartridge for Your Pump
Why the Right Filter Cartridge Matters
Your pool filter cartridge is the workhorse of your filtration system. A mismatched cartridge — even one that physically fits — can reduce flow, strain your pump motor, and leave your water cloudy. Getting the right one the first time saves you money and keeps your pool sparkling.
Step 1: Find Your Current Cartridge Part Number
The easiest way to find the right replacement is to look at the cartridge you already have. Most cartridges have a part number printed or embossed on the end cap. Common Unicel part numbers include:
- C-8414 — fits many Hayward SwimClear and Pentair Clean & Clear systems
- C-7471 — common in Hayward Star-Clear and similar housings
- C-4950 — used in many spa and hot tub filters
If you can read the part number, you can order an exact replacement. Shop our full Unicel filter cartridge collection to find yours by part number.
Step 2: Match by Dimensions If the Part Number Is Worn
If the label is faded, measure these three dimensions:
- Outside diameter (OD) — measure across the widest point of the pleated media
- Length — measure end cap to end cap
- Top and bottom opening size — the hole diameter on each end cap
Cross-reference these measurements against the Unicel catalog or contact us — we're happy to help you find the right match.
Step 3: Verify the Square Footage Rating
Filter cartridges are rated by surface area (in square feet). A higher sq ft rating means more filtration capacity and longer time between cleanings. Match or exceed your current cartridge's rating — never go lower, as this can overwork your pump.
For example, the Unicel C-8414 is a 100 sq ft cartridge designed for high-volume residential pools. If your system calls for it, you can also buy the Unicel C-8414 in a pack of 2 for multi-element filter housings.
Step 4: Know When to Replace vs. Clean
Cartridges can typically be cleaned 5–10 times before they need replacing. Signs it's time for a new one:
- Pleats are torn, frayed, or collapsed
- End caps are cracked or warped
- Pressure stays high even after cleaning
- Water clarity doesn't improve after a cleaning cycle
Shop Unicel Replacement Cartridges
Unicel is the industry standard for aftermarket pool filter cartridges — manufactured to OEM specs and compatible with all major brands including Hayward, Pentair, Jandy, and Sta-Rite. Browse our full selection of Unicel filter cartridges and find your exact replacement today.