How Long To Run A Pool Pump And The Best Times To Do It.

Swimming pools are designed to keep themselves clean with the filter and skimmer systems. These keep out debris that can foster the growth of algae.

A pool pump helps keep your pool water clean, as long as it runs long enough to circulate all of the water in your pool through the filter. The amount of time you need to run your pool pump depends on factors such as pool size, frequency of use, and pump size. Pumps typically don’t need to run for more than 8 hours a day with proper pool cleaning and maintenance.

How long should I run my pool pump every day?

When it comes to running your pool pump, there are many different approaches. You can be an early bird, a night owl, or a combination of the two. Some run their system for long hours, and others try to use it as little as possible.

The industry guideline is to run the pump for at least one turnover every 24 hours.

Every swimming pool is unique. There are a lot of calculations made when building your pool in order to determine the pump sizing, plumbing diameter, and filter sizing. These are important to ensure that your entire pool is being circulated and the turnover rate is satisfactory.

There are pros and cons to each method, so let’s run through the options and determine which is best according to the situation.

Factors that affect how long a pool pump should run:

Other than the pool pump and pool size, the duration of running a pool pump also depends on:

  • The type of pool pump you are using.
  • Whether you use a pool cover or you leave the pool exposed.
  • The amount of foliage around your swimming pool.
  • The season of the year and the local climate.
  • The level of activity the pool gets.
  • Whether swimmers clean up before diving into the pool

An open swimming pool exposed to light will need longer pumping. The same is the case with pools during the summer or in hot climates, or pools surrounded by many trees that shade leaves. On the same note, a swimming pool that gets used often will also need long hours of cleaning.

What Is a Turnover Rate?

The big idea when it comes to running your pool pump is to get all of the water in your pool to go through the filter at least once a day. This is the “ turnover rate ” for your pool, and most systems can turn over the water about 2 – 3 times a day. But, getting your water through the filter is not the only factor involved in cleaning your pool.

If your pool sees heavy use, it is going to accumulate more debris. The more people in your pool, obviously, the dirtier your water will become.

However, if you are not using your pool every day, one turnover will ensure that pool chemicals get distributed, and no algae build-up occurs.

Pool Pump Function:

Your pool pump is used for a few reasons.

  • Filter Algae and Bacteria: It pulls water from the pool and circulates it through the filter to remove particles, algae, and bacteria, then circulates the cleaned water back into the pool.
  • Distribute Chemicals: The pump also helps distribute the chemicals that keep the pool’s water clean and clear and removes debris, carrying it through the pool’s main drain and into a basket, where it can be discarded.

Along with knowing how much water your pump filters, you will need to keep an eye on the weather, temperature, and chemical balance in your pool.

There is a minimum run – time, which makes it easy to establish a baseline for scheduling your pump.

How to Calculate Best Time To Run a Pool Pump?

If you purchased the correct size pump for the volume of your pool, then you’re in luck. You can find the answer in your owner’s manual. However, if you purchased them separately, you may not find easy answers.

  • Length of Pool: First, calculate the volume of your pool. Because above-ground pools only have one depth, it is easy.
  • Rectangular Pools: For rectangular pools, the formula is:

“ Multiply the length by width by depth by 7.5 to get the volume in gallons “

  • Circular Pools: With circular pools, the formula is:

“ Multiply diameter by the diameter by depth by 5.9 to get the total gallons ”

  • Oval Pools: For oval pools the formula is,

“ Multiply the length by width by depth by 5.9 to get the volume in total gallons ”

  • You can also use an online pool volume calculator.

Minimize Pump Lifespan:

You can minimize the amount of time you need to run your pool pump and increase its service life with proper cleaning and maintenance of your swimming pool.

  • Pool covers and automatic pool cleaners: This includes using pool covers and automatic pool cleaners and performing regular cleaning with vacuums, brushes, and skimmers to remove debris and lower the load on the pump.
  • Empty Pool’s Straining Baskets: Empty your pool’s straining baskets daily to reduce the chance of clogged drains, which cause the pump to work harder.
  • Timer: Install a timer on your pump to allow you to automatically run the pump several times a day in short intervals, which helps ensure maximum efficiency.

The Cost to Run a Pool Pump:

If you want to know how to calculate the exact cost of running your specific pool pump, here’s how to do it:

  1. Find your pool pump’s voltage(found on pump label or in manual).

There may be up to 3 different voltages listed. Each one corresponds to different amperage. The highest voltage pairs with the lowest amperage, and the lowest voltage with the highest amperage

Ex.) The pump voltage is 230.

  1. Find your pool pump’s amperage ratings.

Ex.) Amperage is 9.3.

  1. Multiply voltage by amperage to get total watts.

Ex.) 230 x 9.3 = 2139 total watts.

  1. Convert to kilowatts (kW) by dividing total watts by 1000.

Ex.) 2,139 total watts / 1000 = 2.13 kW.

  1. Multiply kW by the number of hours you run your pump a day to get the total kW.

Ex.) 2.13 kW x 10 hours =  21.3 total kW.

  1. Multiply this number by your electrical company’s price per kW (found on your most recent electric bill).

Ex.) 21.3 kW x $ 0.12 = $2.55 per day to run the pump.

Best Time to Run a Pool Pump – Day VS Night:

There are many points of view as to the best time of day to run a pool pump. Some say it should be during the day while others say it is best at night.

Day Time:


  • Reduce Amount Of Chlorine: During the day, the ultraviolet rays from direct sunlight reduce the amount of chlorine in your pool. In some cases, they can lower the level by as much as 90 percent over just a few hours.
  • Counteract Sun Effect: Running your pump during this time helps counteract the sun’s effect and keeps your pool from using up as much chlorine.
  • Kill bacteria faster: If you pump your pool in the daytime, it will kill bacteria more effectively than at night.


  • Cost High: The downside, however, is that the time of day with the most sunlight is also peak hours for most electric companies, causing your monthly bill to increase.

Night Time:


  • Saves Money: Running a pool pump at night decreases your monthly bill.
  • Saves Time: It is estimated that running your chlorinator for 6 hours at night is equivalent to running it for 9 hours during the day.
  • High Chlorine: Nighttime pumping is also ideal when you are doing a chemical treatment. It helps to keep the chlorine levels high.


  • Pump Again In Day Time: After cleaning at night, you should pump it again at least one hour during the day. This will help keep bacteria at bay, which thrives in warm, still water.
  • Not Effective: It is not very effective.

Day VS Night-Time – Which is Best?

The time of day or night, you need to run your pool depends on factors such as your energy saving needs, the length of time you need to run your pool pump, and the pump’s efficiency among other factors.

Since the above are pros and cons of running your pump both at night or daytime.

So in my opinion, it would be best to compromise. It may be effective for you to consider running the pump for half the time it needs to run daily during the middle of the day, when the sun is at hottest, burning off the chlorine,  say 10 pm to 2 pm and the other half of the time at night, say 1 pm to 5 pm, so you can catch up on chlorine production or even get a step ahead for the upcoming day that you would have chlorine when the morning sun hits it.

To Sum Up:

Water circulates in a swimming pool much like blood flows in our body’s circulatory system. The pump and filtration system are the heart and arteries of your pool. The filtration system acts as the highway that the pump powers the water along, making sure it moves throughout the entire space to keep your pool water clear and free of contaminants.

Pool pumps help to sanitize the pool water which is good for everybody’s health.

While running your pool pump for 8 hours a day is ideal, running it for 2 full cycles is even better. Longer filtration cycles mean cleaner water and better circulation. There are advantages and disadvantages for both daytime and nighttime pool pumping.

The choice to run your pool pump during the day or night depends on your personal preference. Generally, experts recommend running it during the day.

Running your pump during the day when the sun is hot enables you to counteract its effect on algae growth. This is also the time when there are many unseen contaminants brought in by the swimmers. When the UV rays hit the chlorine, it results in a pristine and inviting pool for swimmers.


Is it better to run a pool pump at night or day?
It’s always best to run the pool pump during the hottest times of the day. The sun is one of the causes of chlorine depletion in your pool. … If you run your pump during the night when the sun has all day to attack the chlorine that’s standing still in your pool. That can cause algae fast!
How many hours a day should you run a pool pump?
Every pool must turn over at least once a day, so most pool pumps should run approximately 8 hours a day. But here’s the thing, you don’t have to run your pool pump consecutively. You can choose to run it for 3 hours in the morning before you leave for work and another 5 hours in the evening.
Is it better to run a pool pump all the time?
Yes, you have to run your pool pump for at least eight hours every day to complete at least one turnover cycle. But that doesn’t mean it has to be eight hours straight. Again, refer to those non – peak utility hours.
Does a pool pump use a lot of electricity?
Yes. Pool pumps use up to 2,500 kWh per year to circulate and filter the water. The average monthly cost for a 1 HP pump running 8 hours per day in Florida is approximately $30.
Is it OK to run a pool pump 24 hours a day?
A pump does not need to run 24/7 to keep your pool water pristine. If properly sized, a pump should spin through your water in a fraction of the time, allowing it to be dormant for the rest of the day.
How much does your electric bill go up with a pool?
According to the study, at the national average of 11.8 cents per KWh, a pool pump alone can add as much as $300 a year to an electric bill.
Should you run a pool pump in rain?
Yes. You should run your pool pumps because, after heavy downfall, the pool water undergoes different chemical and physical changes. Rainwater can alter the pH and alkalinity level of the pool, and it adds extra water that you don’t need.
How often should I backwash the pool?
As a general rule, you should be backwashing your pool about once a week or in conjugation with your scheduled maintenance.

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