Pentair 179135 vs. 179136 Filter Cartridges: Which 4-Pack Fits Your Clean & Clear Plus?
Every Clean & Clear Plus filter uses four cartridges, not one. So when yours are worn out, you buy a set. The two sets people mix up most are the Pentair 179135 and the Pentair 179136, and they are not compatible with each other.
Here is the short version, then the details.
What's the difference between the 179135 and the 179136?
The Pentair 179135 is the 4-pack for the 420 square foot Clean & Clear Plus. The Pentair 179136 is the 4-pack for the 520 square foot model. Same tank family, taller cartridges on the 520.
The 179135 set is made up of four R173576 elements. The 179136 set holds more media in the same footprint, which is how the tank gets to 520 sq ft. If you drop 420 cartridges into a 520 tank, the manifold won't seat right and water will slip past unfiltered.
How do I know which size filter I have?
Check the label on the side of the tank first. Pentair prints the model number there, and 160301 means you have the 420 and 160332 means you have the 520.
If the label is faded or gone, pull the old cartridge and measure it. Compare that against the set you're about to buy. You can also count on the part number stamped into the plastic end cap of the old element, which is usually still readable even when the pleats are shot.
- Tank says 160301 or CCP420: you need the Pentair 179135
- Tank says 160332 or CCP520: you need the Pentair 179136
- Older EC- prefixed versions of those same filters take the same cartridges
How often should you replace Pentair filter cartridges?
Most sets last two to three seasons with normal use. Heavy bather loads, a lot of tree debris, or chemistry that keeps swinging will cut that down.
Cleaning is not the same as replacing. Rinsing the pleats a couple of times a season is normal maintenance. But the fabric itself breaks down over time, and once it does, no amount of hosing brings the flow back.
Signs your cartridges are worn out (not just dirty)
The clearest sign is pressure that climbs back up within days of a cleaning. If you rinse the set, the gauge drops, and a week later you're right back where you started, the media is done.
Other things to look for:
- Pleats that stay gray or brown after a good soak and rinse
- Fabric that feels stiff, brittle, or slick with oil
- Tears, thin spots, or pleats that have collapsed into each other
- Cracked or separated end caps
- Cloudy water that won't clear no matter what you add
- Weak return flow with a clean pump basket
Any one of those is enough reason to swap in a fresh 179135 or 179136 set.
Can you replace just one cartridge?
You can, but it rarely works out. The four elements share the load, so a single new cartridge next to three old ones just clogs faster while the tired ones keep passing dirt.
The one exception is a brand new set where one element got damaged during install. In that case, matching a single replacement makes sense. Otherwise, replace all four at once.
How to swap the set
Take your time with the o-ring and the clamp band. That is where most leaks start after a cartridge change.
- Shut the pump off and turn off power at the breaker
- Open the air relief valve on top of the filter and let all pressure out
- Loosen the clamp band and lift the tank lid straight up
- Pull the manifold, then lift out the four old cartridges
- Rinse the inside of the tank and check the bottom for cracks or debris
- Seat the new cartridges, reinstall the manifold, and make sure everything sits flat
- Clean and lube the tank o-ring with a silicone-based lube, never petroleum
- Reassemble, leave the air relief open, start the pump, and close the valve once water sprays out
- Write down the new clean starting pressure on the gauge
That last step matters more than people think. Your clean pressure reading is the baseline you compare against later, and it is how you'll know when the next set is worn out.
Which one should you order?
Match the tank, not the price. The Pentair 179135 covers the 420 sq ft Clean & Clear Plus and the Pentair 179136 covers the 520. They cost about the same, so there is no reason to guess.
Not sure this is the right part for your problem? Reach out and we will help you figure out exactly what you need before you spend money on the wrong thing.