Four pool cartridge filter elements of different sizes lined up on a daylight equipment pad

Replacement Pool Filter Cartridge: How to Find the Perfect Fit

Buying the wrong replacement filter cartridge is one of the most frustrating — and surprisingly common — mistakes in residential pool care. There are hundreds of cartridge dimensions in the wild, and brand names like “Pleatco PA50” or “Unicel C-7656” mean nothing if you can’t cross-reference them to what’s actually in your filter. This guide walks through three reliable ways to identify the right replacement, plus the spec numbers that actually matter.

Method 1: Read the part number on the old cartridge

The fastest way. Pull the old cartridge out and look at the bottom or top end cap. Most cartridges have either:

  • A manufacturer model number (e.g., “CX580XRE” for Hayward, “R0462200” for Jandy, “178584” for Pentair).
  • A generic cross-reference number from Unicel (C-prefix) or Pleatco (PA, PRB, FC prefixes).

Send either number to PST and we’ll match the equivalent replacement — usually with a generic or OEM option at different price points.

Method 2: Identify by filter model

If the cartridge is too far gone to read, look at the filter housing. There’s almost always a model label molded into the side or printed on a sticker near the pressure gauge. Common residential filter families:

  • Jandy CL/CV series — uses Jandy R-series cartridges (R0462200, R0462300, etc.)
  • Pentair Clean & Clear — uses Pentair CCP series cartridges
  • Hayward SwimClear — uses Hayward CX series
  • Sta-Rite System 3 — uses Sta-Rite P series
  • Generic / pool-store branded filters — usually accept Unicel or Pleatco direct-fit cartridges

Method 3: Measure the cartridge yourself

If you have no model number and no filter label, take four measurements with a tape measure:

  1. Outside diameter at the widest point of the pleats.
  2. Length from end cap to end cap (don’t include any stub adapters).
  3. Top end cap inner diameter (the hole the cartridge sits over on the manifold).
  4. Bottom end cap configuration — open hole, closed, or specific keyway.

Photograph all four and send them to us. We can almost always match a measurement-only inquiry within a single email back-and-forth.

The filtration area matters too: match the “square feet” rating of the original cartridge as closely as possible. A 100 sq ft replacement in a 150 sq ft housing will technically fit but will need cleaning 50% more often and won’t filter to the same micron rating.

Popular Jandy CS-series replacements in stock

Jandy CS-series filters are one of the most installed in the U.S. Here are the most common replacement sizes:

Jandy CS100 SF replacement filter cartridge element

Jandy CS100 SF Cartridge Kit

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Jandy CS150 SF replacement filter cartridge element

Jandy CS150 SF Cartridge Kit

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Jandy CS200 SF replacement filter cartridge element

Jandy CS200 SF Cartridge Kit

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Jandy CS250 SF replacement filter cartridge element

Jandy CS250 SF Cartridge Kit

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Generic vs. OEM — does it matter?

Honest answer: rarely. Most generic cartridges from reputable manufacturers (Unicel, Pleatco, Filbur) use the same Reemay fabric and end-cap designs as the OEM, at 30–50% lower cost. The main exception is multi-element high-end filters (Pentair Quad DE, Sta-Rite System 3 Mod-D) where the OEM seal geometry is unusually tight — on those, stick with OEM. For straightforward single-element residential cartridges, the generic will perform identically.

Send us a photo

If you’re still unsure, snap a photo of the old cartridge (or filter housing) and send it to PST Pool Supplies. We’ll cross-reference for you and reply with the right SKU, so you only order once.

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