How To Chemically Clean a Pool Cartridge Filter


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Chemicals like calcium and oils from bathers can become embedded in the pleats of your pool cartridge filter. These contaminates are difficult to remove with a standard hose cleaning and may have to be removed chemically. If you are having to clean your cartridge filter every 3-4 days to keep the pool pressure down, it may be time to clean your cartridge chemically with a solution like TSP. This guide shows you how to chemically clean your pool's cartridge filter. Although this description is specific to a Hayward cartridge filter, many of the steps can apply to other models of cartridge filters.

Click Here to View Filter Cartridge Cleaner 

Step by Step


Step 1

OBSERVE HIGH PRESSURE - A high pressure gage reading is a good indication that you need to clean your cartridge filter. If you just cleaned the cartridge within the last week, you need to chemically clean or replace it.

Click Here to View Filter Cartridge Cleaner

Click Here to View Filter Flosser Hose Attachment

Click Here to View Pool Filter Replacement Parts

Step 2

TURN OFF POWER - The first step is to turn off the pool pump to stop the flow of water through the pool filter.

Step 3

RELIEVE PRESSURE -  Next you will have to relieve the pressure that has built up in the pool filter. To relieve pressure turn the air relief valve on top of the filter counter clockwise. Water will spray out initially as you see the pressure on the pressure gauge go to 0 psi.

Step 4

TURN LOCKING KNOB - To access the pool filter cartridge you will have to take the pool filter head off the top of the filter. Turn the locking knob counter clockwise until you feel the pool filter head is loose.

Step 5

LIFT FILTER HEAD - Next lift the pool filter head off the top of the filter. It may be a little hard to lift initially as you break the O-ring seal between the two pool filter parts.

Step 6

VIEW CARTRIDGE - With the pool filter head off, you will see the top of the pool filter cartridge.

Step 7

LIFT OUT CARTRIDGE - Lift the pool filter cartridge straight up to remove it from the pool filter body.

Step 8

CLEAN CARTRIDGE - Set the filter cartridge on the lawn and begin cleaning it with a garden hose. Use a full stray nozzle. A pressure nozzle may be too strong and will cause unnecessary wear on the pleated folds. When spraying, start at the top of the cartridge. Work your way straight down the cartridge to work the debris down and out the bottom of the pool filter cartridge.

Click Here to View Filter Flosser Hose Attachment 

Step 9

PLACE CARTRIDGE IN CONTAINER - Place the cartridge in a tall narrow container. You will want to fill the container with cleaning solution so get one that is as close to the size of the cartridge as possible. The one we have selected isn't quite tall enough to submerge the whole filter, but it will suffice as long as we can clean the majority of the cartridge. Place the dirtiest end (bottom) at the bottom of the container.

Step 10

MIX TSP CLEANER - Using a 5-gallon bucket mix up enough buckets of TSP solution to fill your container. Stir in 1 cup of TSP powder per 4 gallons of water  Some people may be sensitive to this cleaner so, as a precaution, wear rubber gloves and safety glasses. Do not get this solution in your eyes or on your clothes. Read the safety instructions on the TSP box.

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Step 11

FILL CONTAINER - Fill the container to the top of the container to cover as much of the cartridge as possible.

Step 12

SOAK CARTRIDGE OVERNIGHT - Leave the cartridge in the container to soak 12 hrs.

Step 13

REMOVE CARTRIDGE - Using rubber gloves and safety glasses, remove the cartridge from the container.

Step 14

RINSE CARTRIDGE - Rinse the TSP solution off of the cartridge in the grass. As before, wear rubber gloves and safety glasses as a precaution and avoid back splashes to your clothes.

Step 15

REPLACE CARTRIDGE - When you've finished cleaning the pool filter cartridge, replace the cartridge by placing it straight down into the filter.

Step 16

CHECK AND LUBRICATE O-RING - It's always a good practice to lubricate the pool filter head O-ring before replacing the filter head. Lubrication will insure a better fit and extend the life of the O-ring. Rub a thin coat of lubrication on the outside of the O-ring.

Click Here to View Pool Filter Replacement Parts 

Step 17

REPLACE FILTER HEAD - Replace the pool filter head on top of the pool filter. Position the top so that you can read the pressure gauge.

Step 18

CHECK O-RING - When replacing the filter top, watch that the O-ring doesn't bulge out of its grove. This becomes more of a problem as the O-ring becomes older and stretches. If the O-ring is not set properly the top will not close correctly and water will spray out when the pump is restarted. The O-ring should be replaced if this is a recurring problem.

Click Here to View Pool Filter Replacement Parts

Click Here to View Magic Lube (Teflon)

Step 19

TIGHTEN LOCKING KNOB - Hand tighten the locking knob clockwise.

Step 20

TURN POWER ON - Turn on power to the pool pump to repressurize the pool filter.

Step 21

CLOSE AIR RELIEF VALVE - The air relief valve should still be open. As the pressure builds, air will be released through the relief valve. When water starts to spray out of the valve, turn the valve clockwise to close it.

Step 22

CHECK PRESSURE GAUGE - Check the pressure gauge. It typically reads between 10 - 15 psi but this will vary according to the make of pool cartridge filter or its age.

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Step 23

OBSERVE WATER FLOW - A cleaner filter will increase water flow. Your fountain water will be higher and the pool cleaner will move faster and will start climbing the wall again

Step 24

DUMP CLEANING SOLUTION -  Most codes will allow you to pour this solution down the driveway. Leave a hose on to dilute it more just to be sure.


(1 to 20 of 20)

 Posted: 6/28/2021 

Does this cleaning method affect pool water phosphate levels?

InyoPools Product Specialist  Posted: 7/14/2021 

Yes, TSP can add phosphates to your water if the cartridge isn't thoroughly rinsed afterward.

 Posted: 5/8/2021 

Can I use this on my spa filters as well?

InyoPools Product Specialist  Posted: 5/13/2021 

Yes, you may use this method on pool and spa filter cartridges.

 Posted: 8/19/2020 

will TSP damage my perfect lawn

InyoPools Product Specialist  Posted: 8/20/2020 

I don't suggest pouring caustic substances like TSP on your lawn. My rule of thumb, if I have to wear gloves to handle it, chances are it isn't suitable for living things.

 Posted: 3/24/2019 

Can this method of cleaning cartridge with TSP be used on a simple salt pool also?

InyoPools Product Specialist  Posted: 3/25/2019 

Hello Sandi - yes, you can use this same method on a salt pool.

 Posted: 10/3/2018 

Nice job on the pool filter cleaning guide, easy to follow, thanks!

 Posted: 8/3/2018 

Never too old to learn ... Thanks for cartridge clean chapter. I always used just high pressure water. TSP is the way to go periodically.

 Posted: 5/6/2018 

Was able to do all four of my pool filters laying on their side in a wheelbarrow.

 Posted: 12/27/2017 

gene - Unfortunately, we do not sell soaking containers. I used the tallest waste can that I could find that was close to the diameter of the cartridge.

 Posted: 12/23/2017 

do you offer a container suitable for soaking a Hayward CX1200RE cartridge?

InyoPools Product Specialist  Posted: 4/4/2017 

James - You need a container large enough to immerse the whole cartridge. You could have a container half the height of the cartridge and soak the cartridge half at a time but it would take twice as long.

 Posted: 4/2/2017 

Why wouldn't you just put the filter in the bucket mixed with TSP instead of pouring in a separate (Garbage pale) container?

InyoPools Product Specialist  Posted: 9/11/2016 

chemically clean cartridge - Maybe use a chemical cleaner once or twice a season depending on use.

Anonymous  Posted: 9/10/2016 

How often should you do this?

 Posted: 2/9/2019 

wonderful directions...could not have been better. thank you

Anonymous  Posted: 7/3/2016 

Thanks you so much. Very helpful

Anonymous  Posted: 6/22/2016 

Thank you