8 Simple Ways to Optimize Your Pool’s Filtration

How To Fine-Tune Your Pool

There are several simple things you can do to your pool to maximize the effectiveness of your pool’s filtration system without having to buy any new pool gadgets or fancy chemicals. Taking these steps is often overlooked by both homeowners and pool service providers, but can have a dramatic impact on the overall quality of your pool water.

This is a long article with a lot of information, the first part describes turnover, or how your pool filtration and pump system works and the second part outlines the 8 ways you can make it more efficient.

Understanding Turnover Rate and Water Circulation in Swimming Pools

Effective water circulation is critical for filtration, and it’s essential to understand the concept of turnover rate. Turnover rate is the time it takes for the entire volume of pool water to pass through the filtration system. For example, if your filter system runs at 100 gallons per minute and you have a 30,000 gallon pool, your system achieves a 5 hour turnover rate (since 6,000 GPM / 30,000 gallons = 5 hours).

A lightly used residential pool should aim for at least one complete turnover daily. Simply running the pump for longer is a straightforward way to improve water quality—but it’s only effective if your pool systems are already optimized to ensure every drop of water passes through the filter. Also, running the pump more often than is required wastes energy.

Pool Components

Let’s start with some definitions and then we will discuss how to optimize each component, step by step. Pool filtration equipment can be broadly categorized into two groups: suction side and pressure side components.

Suction Side Components

Suction side components are parts of the pool’s filtration system that draw water from the pool and deliver it to the filtration system. This includes:

• Skimmers – Installed in one or more locations around the top perimeter of the pool, these devices pull water from the surface, capturing floating debris before it sinks to the bottom.
• Main Drains – Despite the name, main drains do not actually “drain” the pool. Instead, they are located at the bottom of the pool and help remove water from its deep end, aiding in thorough circulation and debris removal. They work with the skimmers to ensure even water flow to the filtration system.
• Vacuum Line – Some pools have a separate vacuum line dedicated to pool cleaning. This line is typically connected to an automatic pool cleaning system or a manual vacuum head.
• Suction Manifold – This is the point at which all three separate suction side components come together before the pool pump. One or more valves may be installed here to regulate the flow in between the above three components.

Pressure Side Components

Pressure side components are parts of the pool’s circulation system that return filtered and treated water back into the pool. These components include:

• Pool Pump – The heart of your pool! This creates the flow of water through your filtration and heating system.
• Filter Manifold – This is the filter itself and the valve used to control the flow in and out of the filter, such as a multiport or a push-pull valve.
• Heater – Heats the filtered water before it is returned to the pool.
• Chlorinator and/or Salt Cell – Some pools have an automatic chlorine feeder, a salt chlorine generator, or both. It is always installed after the filter and the heater.
• Return Jets – These outlets in the pool walls or floor push the clean, filtered water back into the pool, ensuring proper circulation and distribution.

8 Ways to Optimize Your Pool

Below are eight different components of your filtration and pump systems and ways their operation can be optimized. While it gets a little technical, these are things that nearly anyone can do at home, without any special tools or knowledge:

1. Check Out Your Skimmers
2. Main Drain Inspection
3. Vacuum Line
4. The Suction Manifold
5. Pool Pump
6. Filtration System
7. The Pool Heater / Heat Pump
8. Chlorine Feeders & Salt Cells

➊ Step 1 – Check Out Your Skimmers

The lowly skimmer is perhaps the most overlooked component of all. Our experience has been that 95% of the skimmer type systems out there are not functioning properly. The good news is they can be optimized with a minimum of effort.

• Basket – Many skimmer baskets out there are damaged in some way. Take out the basket and take a look at it. If the basket is cracked, replace it (the part number for the basket is almost always printed somewhere on it). Debris that gets by the basket ends up in the pump strainer, which will decrease the flow through the filter substantially.
• Weir – The weir (aka skimmer door or flap) is just as important as the basket and is designed to enhance the efficiency of debris removal from the pool’s surface. When functioning properly, this hinged flap at the skimmer’s opening assists in removing floating debris from the top of the water. Think of it as both a pump and a one way gate – when the water moves around on the pool surface, the weir opens and closes, drawing the debris into the skimmer. Once the debris moves past the weir, the door prevents it from floating back into the pool when the pump is turned off. When used with a weir, any debris that finds its way into the skimmer will simply float back out to the pool and sink to the bottom when the pump is turned off. Make sure the weir opens and closes freely and is securely attached to the skimmer via the two tabs on the bottom. If it does not, replace it.
• Flow Adjustment Plate – When you remove the pump basket, you will notice that there are usually two ports on the bottom of the skimmer. One port goes to the pool pump (port closer to you), and another to the skimmer equalizer (port closer to the pool). The port to the pool pump should have a good amount of suction. The flow adjustment plate is installed on the suction port. This plate allows you to cover none, some, or the entire port, and its purpose is to increase/decrease flow. Your skimmers should pull about an even amount of water, you do not want one port to pull more than another. By adjusting the plate on each one, you can equalize the flow through each.
• Skimmer Lid – While not tied to the pool filtration, it is an important safety consideration. All lids have brass screws. Inspect the lid for damage and make sure it is securely screwed to its frame.

➋ Step 2 – Main Drain Inspection

There is not much you can do with the main drains with water in the pool, but we can certainly check them out.

• Inspection – Take a look at the grates itself. Are leaves or other debris covering the drain grate? If so, turn off the pump to release them from the grate and scoop it up with your pool leaf rake. How about broken slats? Contact a pool company for replacements if any part of the main drain is missing or broken. Most pool companies can perform repairs like drain grate swaps underwater without having to drain the pool, and the newer style drain grates are designed to allow more flow than older versions.
• VGB Compliance – The Virginia Graeme Baker Pool and Spa Safety Act (VGB Act) is a federal law designed to prevent accidental entrapment and drowning in swimming pools and spas, requiring safer drain covers and grates. It mandates that all public pools and spas use anti-entrapment drain covers that meet specific safety standards. Homeowners should ensure their pool or spa complies with these safety regulations to protect swimmers from potential hazards. If you are unsure if your grates are VGB compliant, contact a pool professional for an update.

➌ Step 3 – Vacuum Line

A wide variety of vacuum systems are available for swimming pools, from the extraordinarily complex in-floor automatic type cleaning systems (common in year-round markets) to the in-wall pressure type robot cleaners, to the very simple manual hose and head setup (common in the Northeast). A guide on these types of systems’ maintenance, setup, and optimization could fill an entire book.

With that said, we recommend that every pool have a manual vacuum head and hose. Despite the advancement of the automatic pool vacuum systems over the years, in our opinion they still have yet to beat the cleanliness that only a manual vacuum process can yield. You can do your pool a great service by getting a quality weighted vacuum head (14”) with adjustable wheels, and a pool specific vacuum hose with a swivel cuff (a 1.5” forty foot pool vacuum hose will work in nearly all situations).

If you have a simple vacuum port in the wall of your pool specifically for vacuuming, make sure that when it is not being used, the control valve on your suction manifold is closed. Unintended water flow through the vacuum line removes flow from the skimmers, allowing more debris to sink to the bottom.

➍ Step 4 – The Suction Manifold

In the front of your pump, we find the suction manifold. This part of the circulation system allows you to adjust the flow between the main drain, the skimmers and the vacuum system.

We want to adjust the valves so that about 75% of the total water flow going into the pump is from the skimmers and the remaining 25% is from the main drains. Of course there is no way to get this exactly right – but closing the main drain ½ way will increase the suction available for your skimmers substantially.

The reason we want to pull the majority of the filtration system’s flow from the skimmers is because most of the nasty things we are looking to filter out are located in the top 18” or so of the water. Think about it – when someone jumps into the pool, anything on their body will rise to the surface.

➎ Step 5 – Pool Pump

Running your filter for longer periods of time is always going to be better for the pool. Far too many homeowners do not run their pool pump often enough. Eight hours per day should be considered an absolute minimum.

• Replace the Strainer Basket – The strainer basket inside the pool pump is in place to keep leaves and other debris that make it past the skimmer baskets from clogging the pump’s internal components. If the basket is cracked or otherwise broken, replace it.
• Lubricate the Pump Lid Gaskets / Drain Plugs – all pumps have a rubber gasket in between the pump lid and the pump itself as well as drain plugs with gaskets of their own. Lubricating these gaskets with a pool-specific lubricant will ensure that air does not find its way into the pump. Pumps that run for a long time shake the plugs loose over time allowing air into the water flow. Any sort of air leak is going to impede flow and impact performance.
• Program Your Variable Speed Pump – Most pool pumps installed in the last few years are VSP’s (Variable Speed Drives). This has been a major advancement in swimming pool technology, yet few homeowners and pool service providers truly understand how best to leverage them.

A VSP allows for the pool pump motor to spin at a user programmable speed. Prior to the introduction of this technology in our industry pool pumps only ran at one speed – maximum. VSP’s take advantage of the “Pump Affinity Law” which describes how changes in the speed of a pump affect flow rate, pressure and power consumption. The flow rate is directly proportional to the pump speed, the pressure is proportional to the square of the pump speed, and the power consumption is proportional to the cube of the pump speed. So what does that mean ?

This example chart may be helpful to help illustrate this concept using an average power rate of 0.13 kWh for a pump that runs 12 hours a day:

These are substantial cost savings for certain! But we would challenge you to take advantage of this in a different way: running the pump at a lower speed for more time per day is going to be better for water quality and the longevity of your equipment. Simply lowering the pump speed but not increasing the time it runs will do wonders for your electric bill but little else.

It is always going to be better to filter for longer periods of time at slower speeds than shorter periods of time at higher speeds, particularly in very hot areas like Phoenix or Houston. Reprogramming a VSP pump can seem intimidating at first – but it is not that hard – really. Download your pump’s manual and go through it step by step.

What you do not want to do is run a VSP at 100% for eight hours a day. You want to run it at 70% for sixteen hours a day, or maybe at 85% for eight hours and 50% for the remaining sixteen hours. We are always shocked at the number of homeowners who are completely unaware that they can have a much cleaner pool and a lower electric bill by leveraging the technology they already have.

If you have an older pool pump that is not a VSP, consider making the upgrade. You can have much cleaner water at a much lower cost.

➏ Step 6 – Filtration System

There are some easy-to-do aspects of maintaining a filter that are often overlooked by homeowners and even pool service providers.

• Pressure Gauges – all pool filters have a pressure gauge, usually 0-60 psi. We can also tell you that at most pools they are long broken. A properly working pressure gauge can assist you by letting you know when it is time to backwash the filter (10 psi for sand / DE over the clean start pressure) or clean the cartridges (20 psi over start pressure).
• Sand and DE Multiport Type Systems – The best check for a multiport is to see if you get water leaking down the backwash line when the multiport is in the filter position. This is a sign that the valve needs to be replaced, as it is not allowing full flow through the filter.
• Cartridge Type Systems – when cleaning the cartridges, use a proper pool cartridge degreaser in conjunction with spraying the cartridges down with water. Think of it this way: sunblock, deodorant, shampoo, soaps, etc., are made to be resistant to just water alone. This sticks to the cartridges and needs to be removed.
• Backwashing Sand Filters – Our experience has been that most people backwash too often for too short a period of time. When backwashing, be sure to allow enough time to pass for the backwash water to turn clear + another minute or two. Note that you only need to backwash the filter when you see a notable pressure increase of at least 5 or 6 PSI.
• Backwashing DE Filters – DE is an amazing filter media because of its ability to filter a particle as small as 4 microns. Sand filters the best you get is 20 microns, while some cartridge filters max out at 15 microns. This is why pools with DE filters always look notably clearer than pools that are on sand or cartridge filters.

However – this extra performance comes at a cost. Most DE filters that have a standard multiport backwash process are very unlikely to get all of the dirty DE out of the tank. It is our experience that about 10 or 15% of the DE ends up staying inside the tank from each recharge, no matter how many times you try to backwash it out. After a few months of operation the filter becomes so packed with DE the water starts to get cloudy, and any DE you add just ends up floating around in the pool, sinking to the bottom.

So – for every 4 or 5 backwashes we recommend that you open up the tank and hose out the grids inside the tank. You will be absolutely shocked how much dirty DE will be inside. Once it is all removed, use a cartridge filter degreaser to degrease the grids. You will be amazed how well this works, but it does take a bit of time. I personally believe that the effort is worth it !

➐ Step 7 – The Pool Heater / Heat Pump

First – let us spend a moment discussing water vs. air temperature. We have always been amazed at people’s passion for pool temperature. Most, in our experience prefer a temperature that is between 85 and 90 degrees. But we have also noticed that most folks only complain about the water temperature when it is uncomfortably hot. Why is that ?

If the air temperature is 88 degrees and the pool temperature is 82 degrees the water will feel cold upon entering the pool. The pool heater is not working !

Conversely, if the air temperature is 60 degrees and the pool temperature is 72 degrees, the water will feel warm upon entering the pool. The pool heater works great !

The three best things you can do for your pool heater are:

• Clean Out the Heat Exchanger – all pool heaters have a copper or nickel plated boiler that is hooked up to the pool plumbing. The heat exchanger should be hosed out at the start of every season to remove soot and other debris that will inevitably build up on the tubes. It has been our experience that pool heaters will begin to burn out the individual components when the boiler is not cleaned on a regular basis. Your pool heater’s I & O manual will have instructions on how to do this. This is, without question, the number one reason that pool heaters get damaged.
• Optimize Your Flow Rate – pool heaters are also required to run at a specific minimum flow rate and are not meant to exceed a certain maximum flow rate. Most pools are pushing way too much water through the heater – thinking that more water is better. The reality is that this causes more condensation to build up on the heat exchanger which then drops onto the burners which creates soot. This soot then clogs the heat exchanger, leading to the damage noted above.
• Balance Your Water – Pools with heaters are much more sensitive to water balance than pools without. This is because the copper tube bundle is much more likely to corrode in unbalanced water than any other component. Maintain a neutral to slightly positive LSI to get the maximum life out of your investment.

➑ Step 8: Chlorine Feeders & Salt Cells

If you are using 3” trichlor type chlorine tablets –

• Never put tablets in the skimmer ! This is probably one of the worst things you can do. The chlorine tablets will destroy pumps, filters and heaters if left in the skimmer because a super concentrated amount of chlorine is introduced into the pool equipment. Use a tablet floater instead.
• If you have an in-line or off-line automatic tablet feeder, do not fill them to the tippity top. We recommend that these feeders never be filled more than 50% of the way full. Too many chlorine tablets does more harm than good. You want to run more water through the tablet feeders at a high setting than the other way around. This prevents clogs and unpleasant respiratory experiences when the feeder lid is opened.
• Never mix different types of chlorine tablets together in the same feeder.

If you are using a salt generator –

• Make sure you have a “sacrificial anode” put in when you have the salt system installed. We cannot stress how important this step is. Salt generators are a fantastic game-changing technology, but salt water is infinitely more destructive than fresh water, even at the low concentrations found in salt water pools. The sacrificial anode does a huge amount towards mitigating this damage.
• Salt pools have different water balance requirements than fresh water pools. The water needs to be kept slightly harder (higher alkalinity, higher calcium hardness) than fresh water pools to avoid becoming corrosive.
• Scale buildup is common on salt cells, but not for the reasons everyone assumes (water balance issues). This is primarily caused by the salt cell being on when the pump shuts off due to its programmed schedule via VSP or the pool pump timer box. As the water drains away from the cell when the pump is turned off, the super high pH byproducts are left behind. This is what generates the majority of the scale. To provent this, you should have your salt cell turn off at least 15 minutes before the pump each day.
• Keep your salt level within 200 ppm of the proper level – Every salt system is slightly different. Some have a salt requirement as low as 2000 ppm while some others can be as high as 6000 ppm. Although we have seen salt cells operate at well below the recommended salt level for extended periods of time, it is important to understand that this puts a lot of stress on the transformer and the plates.
• Aim to keep your cyanuric acid (chlorine stabilizer) at 50 ppm –

Salt systems require a bit more maintenance than fresh water pools, but if you keep these four things in mind you will be in good shape.

If you are manually dosing calcium hypochlorite (granular) chlorine or liquid chlorine on an as needed basis:

• Add your chlorine early in the morning or late in the evening. Sunlight is the primary way chlorine is depleted, particularly for pools that have little shade. Adding it during a period where you get little sunlight helps it get its job done.
• Make sure you maintain your chlorine stabilizer level at at least 50 ppm (or 70 ppm in very sunny dry markets like Phoenix, Dallas, San Diego or Houston). It has been our experience that the cyanuric acid level in markets that receive a lot of rain is a lot lower than this.

Step 9: The Return Jets

The last and final piece of our guide is about our return inlets. Every pool has some sort of fitting or way by which clean filtered water is returned to the pool, usually via an eyeball like fitting that screws into the pool wall or is installed in the pool floor.

Wall Type Return Fittings

At most pools, the eyeballs are pointing in all different directions with little uniformity and all of the jets are pushing a different amount of water. Remember that our goal is to get as much of the water in the pool through the filter as possible, without filtering the same water numerous times. The best way to do this is as follows:

• Point all of the return jets downwards and to the right or the left. An easier way to picture this is to think about a clock face: you want the jets all pointing at 4:00 OR 8:00. This will ensure that when the water is returned to the pool it flows in a circular motion around the pool. This also assists in pushing the water on the surface into the skimmers.
• Size the eyeball part of each return jet appropriately – you will notice that every return jet will return water at different pressures – the further the return jet is from the pool equipment the less pressure it will produce. Ideally, you want each return jet to push evenly. This can be accomplished by increasing (or decreasing) the size of the opening of the eyeball fitting. They are available in five sizes from all of the major brands – the largest size is 1” and the smallest is ⅛”. The best place to start is to order one eyeball of each size. If you have five return jets, order two jets in each size. This takes a good bit of experimentation to get it right, but remember to keep the overall goal in mind: how can I make each of my return jets push evenly ?

Floor Type Return Fittings

Some pools – particularly those in areas that do not have a ton of foliage – use floor returns. These are circular ports that are installed in the pool floor, usually about 2” wide. Although they are not as effective at assisting with pushing debris into skimmers as eyeball fittings, they are much better at ensuring more of your pool water makes it into the filter during a turnover cycle by their design.

• Suction Manifold Setup – At these types of pools, it is extra important to ensure that most of the flow into your pump is coming from the skimmers. If the water is being returned via the floor, you do not want most of the flow into the pump coming from the bottom drains. Adjust your skimmer and main drain valves to get 75% of the water flow from the skimmer system and the remaining 25% from the main drain system.
• Adjustment – Most floor return fittings are adjustable via a “spinner” type valve in the center of the fitting. When the spinner is spun open – you get more water flow. When the spinner is spun closed – you get less water flow. You can adjust these fittings with a standard Phillips head screwdriver. Just like the eyeball fittings, you want the ones closer to the equipment to push just as evenly as the ones furthest away from the pool equipment. Of course, this can be tricky to do underwater!

Conclusion

The funny thing about pool maintenance is that 95% of the effort required to operate a pool only gets you 50% of the way to a properly working pool. Putting forth that last 5% of effort needed really delivers on that last 50%. Take these steps and you will be shocked at how much better your pool looks.