Pool Filters

General Pool Filter Questions: What is the difference between a Sand, Cartridge, or D.E. filter Should I upgrade to a larger filter? Should I do anything to my filter or equipment when I close my pool down for the winter? Is there any way of sealing a leak in a filter tank? Working with your Cartridge Pool Filters How do I clean my filters cartridge? Working with your D.E. Pool Filters How often should I clean my D.E filter? How often should I change my D.E.? I seem to have to regenerate my D.E. filter frequently. Could too little D.E. be the cause? I have a D.E. filter. Do I need to add diatomaceous earth to the filter through the skimmer before or after I backwash? How does the micron filtration rating for a D.E. filter compare with that of a cartridge filter & sand filter? How do I Backwash my Hayward D.E. Filter Working with your Sand Pool Filters Why is dirt passing through my sand filter? I have a 10 year old sand filter. How can I determine if the sand needs to be replaced? I have a sand filter and I'm getting a lot of sand in the bottom of my pool. Do you think there is something broken inside the filter, or do I have another problem? How can I find out how many pounds of sand I need to put in my sand filter? How do I change the sand in my top mount sand filter? How do I Backwash my Sand Filter? Trouble Shooting your Hayward Swimming Pool Filter My sand pool filter is running at high pressures. My pool sand filter is running in short cylces. There is sand at the bottom of the swimming pool My cartridge filter will not clear algae from the pool. My DE filter is running at high pressures and has a slow flow of water returning back to the pool. My DE filter short cycles even after I backwash or regenerate and recharge. My DE filter is leaking back into the pool My DE filter has short cycles when vacuuming Will backwashing or regenerating my DE filter thoroughly clean my filter? The swimming pool won't stay clear . My swimming pool filter is noisy. My Vari-Flo valve leaks to waste. My filter pressure gauge has dropped below normal for a clean filter? The valve on top of my screw top fiberglass filter keeps popping off when the pressure reaches 15psi. What can I do to correct this?

Depending on the length of your pool swimming season we recommend replacing your fiter cartridge every 1 - 2 seasons. You can greatly increase the life time of your cartridge with the proper cleaning and care of the cartridge. Click for our pool filter cartridges. Filter Flosser Cartridge Cleaning Tool Your Cartridge will last longer $34.99 click here for details How To Use the Filter Flosser How To Clean a Pool Cartridge Filter How to Replace D.E. in your D.E. Filter How to Replace Sand in your Sand Filter How to Install a Pool Sand Filter How a Multiport Valve Operates How to Backwash a Sand Filter

General Questions:

Q: What is the difference between a Sand, Cartridge, or D.E. filter

A: Sand - Filter Range 20 to 40 microns. The oldest and most popular method of filtration is sand. Sand filters use a special filter sand, normally .45 to .55 mm (also known as pool-grade #20 silica sand), because it has sharp edges that serve to separate particles, allowing filtration to take place. Sand filters are the least expensive of the three types of filters but only filters particles down to 20 to 40 microns in size.

Cartridge - Filter Range 10 to 20 microns. Cartridge filtration has been available for a relatively long time, and recently has begun to enjoy rapid growth and acceptance. When water passes through a cartridge filter, dirt is screened out at the surface of the cartridge element. When clean, the element will trap larger particles, with finer particles being filtered out as the pores of the element become clogged by the larger debris. The cartridge element can be removed and cleaned by pressure washing inside and out with a garden hose.

D.E. (Diatomaceous Earth) - Filtration Range 1 to 3 microns. Many pool professionals consider D.E. filtration to be the finest, because it is capable of removing smaller particles than either sand or cartridge. Diatomaceous earth is a porous powder with microscopic openings, that, when magnified, look like tiny sponges. Clear water can pass through these openings but particles, as small as one to three microns are trapped the first pass through the media. All D.E. filters have internal elements that become coated with D.E. It is this "filter cake" that strains dirt, dust, algae and some forms of bacteria from the water. Similar to sand filters, when a D.E. filter becomes dirty, it is cleaned either by backwashing the clogged D.E. to the "waste" line or regenerating and draining. To restore filtration, a fresh "charge" of D.E. is added to the filter.

Q: Should I upgrade to a larger pool filter?

A: Pool water filtration is the heart of your water care system. Depending on the size and style of the filter selected, you can achieve energy savings and improved water clarity by reducing the time and energy your pump must exert to cycle the entire body of water in your pool during a 12-hour period. Save energy and time by selecting a larger filter versus a standard filter size. A larger filter provides more filtration area, thus reducing back pressure buildup over time, and strain on your pump. A larger filter can extend the periodic maintenance cycle, thus saving the homeowner valuable time.

Q: Should I do anything to my filter or equipment when I close my pool down for the winter?

A: Cleaning your sand or D.E. filters when you close your pool for the season will ensure that they are ready for action when you open your pool the following summer. When closing your pool for the season, coat all accessible o-rings, rubber fittings, and gaskets with a silicone O-ring lube to keep them from drying out.

Q: Is there any way of sealing a leak in a filter tank?

A: Unfortunately, there is no way to safely seal a leak in a filter tank. The best option is to replace the tank.

Working with your Cartridge Filter

Q: How do I clean my filters cartridge?

A: When cleaning cartridge filters, soak them in a cleaning solution for 24 hours, then hose them off before reinstalling.

Working with your D.E. Filter

Q: How often should I clean my D.E filter?

A: D.E. filters should be disassembled and cleaned at least once per season.

Q: How often should I change my D.E.?

A: You should change your D.E. after backwashing your filter.

Q: I seem to have to regenerate my D.E. filter frequently. Could too little D.E. be the cause?

A: Yes, too little D.E. could cause your pressure to go up. Too little D.E. would not coat the grids and the debris that you filter would get embedded in the grid cloth causing it to become clogged. You probably should take the grid assembly out, clean it off, and soak it in a solution of TSP and water for 12 hours. After soaking, spray off the grid assembly thoroughly. Finally, reassemble it and precoat it with the correct amount of D.E. (refer to you owner's manual). You should see a big difference in the performance of the grid assembly.

Q: I have a D.E. filter. Do I need to add diatomaceous earth to the filter through the skimmer before or after I backwash?

A: Diatomaceous earth should be added to the filter after backwashing.

Q: How does the micron filtration rating for a D.E. filter compare with that of a cartridge filter & sand filter?

A: A sand filter rates at approximately 20-40 microns while Cartridge filters are rated at approximately 10-20 microns. D.E. filters are rated at approximately 1-3 microns. So you will get better filtration with the D.E. filter. You can make a cartridge filter a little more efficient by adding 1/4 to 1/2 pound of D.E. through the skimmer.

Q: How do I Backwash my Hayward D.E. Filter?
Models EC30, EC40, EC50, EC60, EC65, and EC75

• Turn off your pool pump.
• Open the pool filter backwash valve.
• Use the pool filter bump handle slowly 15 times.
• Turn on your pool pump and run it for 2 minutes.
• Turn off your pool pump.
• Use the pool Filter Bump handle slowly 15 times.
• Turn on your pool pump 1 minute.
• Turn off your pool pump.
• Close the pool filter backwash valve.
• Turn your pool pump back on.
• Add D.E. to the pool skimmer located closest to pool pump.
• For Hayward EC-40 / EC-50 Filters use 3 lbs of DE
• For Hayward EC-65 / EC-75 Filters use 5 lbs of DE
• Add D.E. to the pool skimmers slowly. Don't clog them !
• Check swimming pool water level after backwashing - add more water if necessary.

Working with your Sand Filter

Q: Why is dirt passing through my sand filter?

A: A number of things could be causing the problem. It could mean that a lateral is cracked or broken, or a valve may need servicing. Or, air may be passing through the filter, causing a channeling effect that permits dirt to get by the filter. In the latter case, there may be nothing wrong with the filter.

Q: I have a 10 year old sand filter. How can I determine if the sand needs to be replaced?

A: The general recommendation is to backwash your filter when the pressure reaches 10 psi over the initial start up pressure. For example, if the start up pressure is 15psi, you should backwash when the pressure reaches 25psi. If the pressure does not return to the start up pressure after backwashing, it is time to change the sand.

Q: I have a sand filter and I'm getting a lot of sand in the bottom of my pool. Do you think there is something broken inside the filter, or do I have another problem?

A: If you are getting a lot of sand in the pool there may be a lateral broken in the bottom of the filter. If this is the case, the lateral(s) will have to be replaced.

Q: How can I find out how many pounds of sand I need to put in my sand filter?

A: Refer to your filter owners manual

Q: How do I change the sand in my top mount sand filter?

A: To replace the sand in your filter you must first disconnect the pipes going into the valve on top of the filter. Next, unscrew the complete valve counter-clockwise. Once the valve has been removed, you will be able to see the sand bed. The best way to remove the sand is to either use a portable vac or just dip it out with a small can. Once the old sand has been removed, fill the tank 2/3 full of water and just pour the new sand in. DO NOT get sand in the vertical pipe sticking up from the bottom of the filter tank.

Q: How do I Backwash my Sand Filter?

• Turn off your swimming pool pump.
• Turn your swimming pool filter multiport valve to the backwash position.
• Open your backwash gate valve.
• Turn your swimming pool pump on and run the pool pump for 2 minutes.
• Turn swimming pool pump off.
• Turn swimming pool filter multiport to the rinse position.
• Turn swimming pool pump on and run it for 1 minute.
• Turn swimming pool pump off.
• Turn pool filter multiport valve to the backwash position.
• Turn swimming pool pump on and run it for 2 minutes.
• Turn pool pump off.
• Turn filter multiport valve to rinse position.
• Turn pool pump on and run it for 1 minute.
• Turn swimming pool pump off.
• Turn filter multiport valve to filter position.
• Close filter backwash gate valve and turn pump on
• Check swimming pool water level after backwashing - add more water if necessary.

Trouble Shooting your Swimming Pool Filter

My sand pool filter is running at high pressures.

• Follow the backwashing instructions in your Owner's Manual. The sand bed may be clogged with mineral deposits that will not backwash away. Some calcium based chlorines and other alternative sanitizers will build up in your sand bed, and will require more frequent backwashing and changing of the sand.
• Before you replace all the sand in your pool filter, try removing approximately 1" of the top layer of the sand, replace with the exact amount of sand you removed. Normal life span of the sand is about 4 - 5 years.
• You may have to clean your swimming pool filter system with a special filter cleaner, check with your pool dealer for proper procedures.
• Check to see if there is a closed or partially closed valve along your return piping, open the valve.
• Your swimming pool pump may be too small to provide sufficient flow for proper backwashing. Your filter will function, but a lower design flow rate will cause your system to backwash improperly. Check the output of the pump to be sure that it equals your filter's design flow rate. Replace the pump if it is too small.

My pool sand filter is running in short cycles.

• Improper backwashing could be the reason. Always backwash until the water runs clear in the valve's sight glass, usually about two minutes.
• You may have have algae causing the pool filter to clog. By testing the swimming pool water balance with a test kit and super chlorinating, you should solve this problem.
• NOTE: Some test kits may provide inaccurate results, we suggest taking a water sample to your pool dealer for evaluation. Be sure to take a water sample before shocking the pool.

There is sand at the bottom of the swimming pool.

• The sand you are using could be too small, which will go through the filter system, then back into the pool. Remove the sand and replace it with the proper grade of sand - #20 Silica or 45-55mm pool sand, which can be found at your local pool dealer.
• Your swimming pool pump may be too big for your filter. During backwashing the pressure can cause the sand to rise high enough to overflow into the standpipe, allowing sand to flow back into the pool. Refer to your Owner's Manual for the correct amount of sand for your filter.
• There could be a loose lateral located at the bottom of your filter. Tighten any loose laterals, replace if broken.
• Most calcium based chlorine, both powder or tablets, contain from 30 - 35% of what is called inert materials. This is calcium residue or dust, which many pool owners mistake for sand. You can confirm this by following these steps: During vacuuming, use a hand vac and pole. As the vac head approaches, , the sand will lay on the bottom, and will allow itself to be picked up. Most calcium residue will scatter away from the vac head as you try to pick it up.
• If you have this problem, we recommend that you put extra water in your swimming pool and vacuum to the waste line. If you vacuum to the filter, some of it will be trapped on the sand surface, allowing dust to get back into your pool.

My cartridge filter will not clear algae from the pool.

• The three filter types will clear up algae, provided it is not in a live state. Consult your local pool dealer for the proper chemicals to help rid the algae. Most cartridge filter problems are caused by dirty, clogged or abused elements. Either clean the elements, or replace if torn or damaged.

My DE filter is running at high pressures and has a slow flow of water returning back to the pool.

• The DE pool filter is loaded with too much debris or algae and needs backwashing or regeneration. If this problem persists and you notice the filter gauge pressure rising from 7 - 10 psi above your beginning pressure, you need to regenerate your filter. Refer to your Owner's Guide for further instructions or consult your pool dealer for service.
• Your swimming pool pump output might exceed the design flow rate of the pool filter. Make sure the pool pump is correctly sized for your filter.
• If there is algae in the swimming pool, super chlorinate, backwash or bump/drain and recharge as needed. Make sure you are properly backwashing on your vertical grid filter. Refer to your Owner's Manuals for instructions.

My DE filter short cycles even after I backwash or regenerate and recharge.

• The swimming pool filter elements may be clogged because of an accumulation of chemical deposits. Clogging is accelerated if chemicals are fed through the skimmer, operating your filter too long without DE after starting the pump, or operating the filter without DE. DE must be added as soon as the filter is full of water, and the pump is putting out a steady stream of water. Refer to your Owner's Guide for the amount of DE your filter requires.
• Biguanide based sanitizers (i.e. Baquacil, SoftSwim) can cause short cycling.

My DE filter is leaking back into the pool

• Be sure that the suspected material on the pool floor is actually DE. Pollen, chemical residue and plaster dust often look like DE.
• You may have a tear in your filter elements, replace if necessary. Make sure that you assemble the internal parts properly!
• Check for air leaks, as this will cause the system to leak DE back into the pool. If there are air leaks, install a check valve between the pump and the filter valve.

My DE filter has short cycles when vacuuming

This is normal if the swimming pool contains very dirty water. Backwash or regenerate and recharge more often. If there is a presence of live algae, add enough chlorine sanitizer to control this growth, then vacuum. The presence of alum or floccing agents will clog the filter. Vacuum so as to bypass the swimming pool filter. Do not use floccing agents with DE pool filters.

Will backwashing or regenerating my DE filter thoroughly clean my filter?

No, you must thoroughly clean the elements at least once a year. You can clean your filter elements using automatic dishwasher detergent. Remove the elements from the swimming pool filter, according to the instructions in your Owner's Guide, and hose them off with a forceful stream of water from your garden hose. Fill a large plastic container with the detergent, using about a 1/2 cup and warm water. Soak the elements for approximately 3 - 4 hours. After soaking, rinse off the elements again. Re-assemble your filter according to the instructions in your Owner's Guide. Note:do not soak elements in muriatic if the pool uses Biguanide products. This will damage the swimming pool filter.

You may choose to clean the elements with muriatic acid or other commercial pool filter element cleaners, mix according to the package instructions. Use extreme caution when handling any cleaning agents, as they can be harmful to the eyes, skin and clothing. After cleaning, thoroughly rinse all elements with cold water.

The swimming pool won't stay clear .

• Your pool chemistry may be out of balance, allowing algae to multiply.
• The flow rate through the filter may be low due to clogged or undersized piping. Cleaning the lines or changing to larger pipes will correct this problem.
• Your filter operation time may not be long enough to compensate for heavy use or hot weather. Try running your filter for 24 hours to clear the water, then adjust to less running time.
• Your pump may be hooked up to the wrong port on the multiport valve. If incorrectly installed, the filter will be flowing in reverse. Be sure the pump is connected to the port marked "pump" on the valve.
• You could be backwashing too often. Backwash only when the pressure rises 7 - 10 psi over the starting pressure, or when the return flow back into the pool becomes low.

My swimming pool filter is noisy

An oversized pump may cause noise in your filter valve due to excessive flow. To test, hold your hand partially in front of any returns at the pool wall. If the noise subsides, this will confirm that the problem is excessive flow. It can be remedied by by installing smaller eyeball fittings in the return(s), changing the pump impeller size in the pump, or change to a 2-inch control valve.

My Vari-Flo valve leaks to waste

The valve seat gasket inside the valve has become worn or loose. You may choose to do this yourself or contact your local pool dealer for service. How do you replace the gasket? You will need a new gasket, obtained from your local dealer, some Krazy Glue, and a sharp 1/8-inch wide flat bladed screwdriver. NOTE: Mark the top and bottom of the valve with a marking pen. It's very important that you do not change the location of the cover when re-assembling. Remove the cover, usually six screws. Using the screwdriver, scrape out every last part of the gasket and cement, in order to get back to a clean flat surface. Put a fair amount of crazy glue on the flat side of the gasket. Place the gasket, flat side down, back into place - let dry for one hour minimum.

Q: My filter pressure gauge has dropped below normal for a clean filter?

A: If your filter pressure gauge indicates that pressure has dropped below the normal reading for a clean filter, check to see if you have a clogged pump or skimmer basket.

Q: The valve on top of my screw top fiberglass filter keeps popping off when the pressure reaches 15psi. What can I do to correct this?

A: A valve blowing off the top of the filter is a serious problem. We highly recommend that you purchase a new filter immediately. We would not recommend running the filter under these conditions.

To purchase a Swimming Pool Filter please follow one of the links below

• Hayward Filters
• Jacuzzi Pool Filters
• Jandy Filters
• Pentair Pool Filter
• Sta-Rite Pool Filters
• Pool Filter Cartridges