How Long Should You Run Your Pool Pump?



Running your pool pump is the first step in Pool Maintenance 101. Every savvy pool owner knows that this is one of the easiest parts of owning a pool: cleaning your pool without breaking your back. The science to running your pool pump, however, can be a bit more ambiguous.

Every pool is different and every pool filter has its own specifications. Knowing how long to run your particular pool pump and what time of day makes the most sense can actually save you a bundle in the long run. 

Answering these two questions can make a huge difference to your pool chemistry and more importantly, your utility bills. So, how long should you run your pool pump? 

Survey Says… Forever

The optimum amount of time to run your pool pump is 24 hours a day, 7 days a week, forever and ever and ev— you get the point.

Doing so would keep your water constantly circulating, your filter perpetually filtering, and your chemicals living their best life. Unfortunately, we’re not all living in golden houses with  $100 bills falling out of our pockets. 

Running your pool pump is expensive. It takes a lot of energy and can really hit your utility bills… hard. It is, however, an essential part of pool care so the best way to approach the question of “How long should I run my pool pump?” is with “SET”. Size, Efficiency, and Time.

  • Size (volume) of your pool – for gallons per hour measurement
  • Efficient Pump for energy conservation
  • Time of Day to run the pump

We’ll get into what all of this means and walk you through it step by step. But first, let’s see how your pool pump works and why all of this matters. Ready to dive in?

How Your Pool Pump Works

Your pool pump is the circulatory system of your pool. Keeping the water moving as much as possible assures that your pool will not become a stagnant bog, prone to attracting all sorts of insects, algae, and bacteria.

The movement of water enables your pool filter to do its job: to filter out debris and bacteria that might have snuck into your pool water. Even if you have the best, top-of-the-line pool filter, it can’t clean your pool unless you run your pump.

Running your pool pump every day is a must for any pool owner. But in order to determine how long is long enough and the best times for your lifestyle — we need to dig a little deeper.

What is “Turnover Rate”?

And how do we calculate it?

Turnover rate is the number of hours it takes to all the water in your pool through the filter once.

To determine the turnover rate, first, we have to calculate the volume of your pool. If you don’t know how many gallons of water your pool holds, you can easily calculate it here.

The next part is to check your pool pump. How fast does it pump water through your filter? 

Start your stopwatch and your pump. When your entire pool has gone through your filter, stop the timer. That’s your turnover rate. Just kidding, that’s crazy (and impossible).

Instead of sitting by your pool trying to figure this out with a stopwatch, we turn to math (*gasp*).

Once you’ve figured out the volume of your pool, divide the total by 8 (hours) to determine the number of gallons per hour (GPH) that need to be pumped. For example, if you have a pool with 20,000 gallons you’ll need a pump that can move 2,500 gallons in an hour.

[20,000 ÷ 8 = 2,500]

GPH is a little annoying to deal with because most pumps talk about water movement in gallons per minute (GPM), so then we divide that by 60. There are 60 minutes in an hour right? 

[2,500 x 60 = 41.666666666]

You probably don’t need the 6 repeating, so lets round it up to 42. So in our example, you’ll need a pump that will pump at least 42 GPM to cycle your entire pool in an 8 hour period. 

The Perfect Pump for the Job

The overall goal for your pool pump is to cycle the entirety of your pool’s water through the filter at least once per day. 

If your current pool pump is capable of turning over all of the water in your pool in 8 hours— that’s great! However, if what you have right now isn’t doing the trick, you may need to run your pump longer to turn over all of the water or you may need to start looking into an upgrade.

Eight hours is a good time to shoot for to allow your pump to cycle through the entire pool. Any longer than that and you’re going to spend a lot of money running your pool pump inefficiently (and nobody wants that). 

We Need More Power, Captain!

On the flip side, you want to make sure your pump doesn’t overwhelm the filtration system. If you hook up a fire engine’s pump (500-2000GPM) you’ll cycle the entire pool in a half hour. You’ll also blow up your filter. 

Just like Goldilocks and the three bears, you have to find the perfect balance: not too hard and not too soft. Check your filter specs and see what kind of flow rate it handles and what’s best for your system. It should all be in the manufacturer’s information.

If everything isn’t matching up, it’s time to do some math. 

Is your pump not powerful enough to cycle through in an 8 hour period? 

Or can your filtration system not handle the pressure? 

If the answer to either of these questions is no, it may be time to look at upgrading one or both of those systems. It’ll save you money in the long run. 

Single, Dual, or Variable Speed Pool Pumps

Let’s talk about speed real quick. 

If you’re trying to be as efficient as possible and to save some money, you’ll need to figure out what speed(s) your pump is capable of. 

If your pump is a bit older, chances are it’s a single-speed pump. It runs at full blast right out of the gate. It’s not really efficient, but the pump itself is cheap. 

Dual speeds pool pumps are much more efficient. They have a full power setting for heavy-duty tasks like vacuuming and a low power mode that can be left on for hours to filter and circulate your pool. They’re much more efficient than a single speed but the pump itself is usually a bit pricier. It will save you on electricity and headaches later on down the line, though. 

Variable speed means just that: you can crank up the speed of the pump or slow it down. It uses the same concept as the dual speed pump but with much more control. Although it has a higher upfront cost, it will be much more efficient for your pool and energy-saving for your wallet. 

If you don’t have at least a dual speed pump, it’s worth looking into if you’re in the market for an upgrade. A single-speed pump will do the trick but it’ll be costing you more money every time you run it for the lifetime of your pool. If you have a small pool it’s probably not a big deal but for larger pools, it can add up. 

What Time of Day is Best?

The generally-accepted rule of thumb for running your pool pump is to get that sucker going for at least 8 hours per day. This doesn’t mean, however, that you have to run it for a consecutive 8 hours or that it has to be at a certain time of day. 


Depending on your electricity provider and where you live, you may have what’s called “on-peak” and “off-peak” electricity times during the day. 

If you’re not sure what these are, it’s something you should probably be familiar with, even if it’s just to get the adulting merit badge. Utility companies price with a peak system using the simple supply and demand concept. When there’s more demand on the power grid the price goes up. When there’s less demand the price goes down. Pretty simple right?

During the day, after everyone gets home from the old 9-5, what do people do? Turn on the TV, hit the AC, play some Xbox, or whatever. Chances are, you’re using a lot more electricity than when you were at work. That’s why there are certain hours of the day that the utility companies charge more or less per watt used. 

If you decide to turn on your pool pump during these peak times, you’re spending a lot of money that you don’t necessarily need to spend. 

It’s a good idea to contact your electricity provider to find out if on/off-peak hours are part of your utility plan. If so, you can schedule your pool pump to run during off-peak hours, saving you a decent chunk of change.

To make it even easier there are pool pump timers that you can set to turn your pool pump on and off at specific times. 

Space it Out

The goal is to cycle your pool water through your filter at least once per day. Unlike a lot of other maintenance work, you can be a little lazy about it. 

By lazy, I mean you don’t have to do it all at once. 

Especially if your pool pump has a timer, just like the Ronco Rotisserie you can really just set it and forget it! Set your pool timer to run during off-peak hours even at different times of day, if needed. If you don’t have a pool timer, this means you can manually turn it on and off when electrical prices are cheaper or after you’ve added pool chemicals.

The main point is it doesn’t have to happen all at once. As long as your pool water is completely filtered through at least once per day, you’ll be swimming in crystal clear waters. 

Early Morning or Evening?

During the middle of the day? 

The time of day that you run your pump doesn’t really matter too much. The filtering elements in your system are hidden away from the light of day anyway, so having the sun or moon in the sky doesn’t really make a lot of difference. 

When it does make a difference is if you need to put chlorine in your pool. As a savvy pool owner, you probably know that chlorine and sunlight don’t really mix. The sun burns off chlorine nearly as fast as you add it, rendering it useless in your pool. So if you are shocking your pool or adding chemicals, typically you want to add those after the sun’s gone down.

Whenever you add chemicals to your pool, it’s a good idea to run your pump long enough to circulate the chemicals throughout the water. It would be pretty weird to have perfect pool chemistry near the steps and to have nasty algae starting to grow over in the deep end. 

So does morning or evening matter? Only if you’re putting in chlorine or pool shock. 

Can’t Stop, Won’t Stop

It may not seem like a tricky question but there actually are a few factors that go into running your pool pump. Now that you know the ins and outs of proper pool pump etiquette (say that three times fast) and can make the most of the system you have or look into investing in an energy-saving upgrade.

Knowing how long to run your pump, what time of day makes the most sense, and what kind of pump is right for your pool can make all the difference to the cleanliness of your pool and to your bottom line.

Categories: Pool Care, Pool Maintenance