How to Find the Right Pool Filter Cartridge
Use the filter model number, cartridge part number, dimensions and end-cap style to avoid ordering the wrong replacement cartridge.
```The safest way to find the right pool filter cartridge is to identify the filter model number on the tank label first, then match the manufacturer’s replacement cartridge. Cartridge dimensions help confirm fit, but they should not be the only method because many cartridges look similar but do not seal correctly.
Ordering the wrong filter cartridge is easy. Many cartridges are the same general shape, close in height and close in diameter, but the end caps, core, pleat count and sealing surfaces can be different.
That is why Aqua Terra Backyard recommends matching by filter model whenever possible.
Where to Find the Filter Model Number
```Tank Label
Look for a label on the filter tank showing the brand, model and sometimes the filter area.
Old Cartridge
The cartridge may have a printed part number, brand number or aftermarket cross-reference.
Owner’s Manual
The parts page often lists the exact cartridge part number and quantity required.
Common Pentair Clean & Clear Plus Cartridge Matches
```| Filter Model | Filter Area | Common Replacement Cartridge | Quantity Needed |
|---|---|---|---|
| CCP320 | 320 sq. ft. | R173573 / PCC80 | 4 cartridges |
| CCP420 | 420 sq. ft. | R173576 / PCC105 | 4 cartridges |
| CCP520 | 520 sq. ft. | R173578 / PCC130 | 4 cartridges |
These three filters are commonly confused because they are all part of the Clean & Clear Plus family and all use four cartridges. The cartridges are not interchangeable between the 320, 420 and 520.
```How to Measure a Pool Filter Cartridge
```If the label is gone and the old cartridge has no readable part number, measurements can help narrow down the match.
When Should You Replace a Pool Filter Cartridge?
```Torn Pleats
Rips, holes or collapsed pleats can allow debris to bypass the media.
Broken Bands
Broken support bands allow the pleats to spread and deform.
Damaged End Caps
Cracked or warped end caps can prevent the cartridge from sealing correctly.
Pressure Rises Quickly
If pressure spikes soon after cleaning, the cartridge may be worn, scaled or oil-loaded.
Cloudy Water
If chemistry is correct and flow is good, worn media may be part of the problem.
Stains Do Not Rinse
Deep oils, scale or embedded debris may not clean out with normal rinsing.
Photos to Send Aqua Terra Backyard
```If you are not sure which cartridge fits, send these photos before ordering:
- Filter tank label
- Full filter from a few feet back
- Old cartridge standing upright
- Top end cap
- Bottom end cap
- Any printed numbers on the cartridge
- Length, outside diameter and inside diameter measurements
Pool Filter Cartridge FAQ
```Can I find a cartridge by pool size?
Are all cartridges with the same dimensions interchangeable?
How many cartridges does a Pentair Clean & Clear Plus use?
Can I replace only one cartridge in a four-cartridge filter?
Why does my pressure stay high after cleaning?
Need Help Matching a Cartridge?
Send Aqua Terra Backyard your filter label, old cartridge photos and measurements. We can help identify the correct cartridge before you order.
Shop Pool Filter Cartridges Shop Pool FiltersAlways verify the current manufacturer manual and filter label before ordering replacement cartridges. Filters are pressurized vessels and must be depressurized before opening.