How to Calculate Pool Pump Run Time

Not sure how long to run your pool pump? That’s okay. A lot of people aren’t sure.

Your pump keeps the water clean. It helps move the water through the filter. It also helps spread the pool chemicals so everything stays safe. If you don’t run it long enough, your water might get dirty or green. If you run it too much, you might waste power and money.

The good news is, there’s a simple way to figure it out. You don’t need to be a pool expert. Just a few numbers and you’ll know how many hours to run the pump.

There are also things like robot pool cleaners handy. They can even clean the bottom and sides of the pool for you, relieving some stress on your pump.

Why Pool Pump Run Time Matters

The pump draws dirty water into the pool, sends it through the filter, and returns the clean water to the pool. It also distributes, for example, chlorine to keep up with the germ-fighting processes.

If you don’t run the pump long enough:

The water might get cloudy

• Algae might grow
• The pool might smell funny

If you run the pump too long:

• You waste electricity
• You wear out the pump faster

Things that change how long your pump needs to run:

• How big is your pool 
• How many people swim in it
• How hot the weather is
• How much dirt or leaves get in

Using a robot cleaner can help with this. Some can clean your whole pool on their own. That means your pump doesn’t need to work as hard.

Step 1: Calculate Pool Volume

To calculate pool volume, for rectangle pools, use this: length × width × average depth × 7.5.

For round or oval pools, use this: length × width × average depth × 5.9.

Let’s say your pool is 20 feet wide, 40 feet long, and about 5 feet deep. 20 × 40 × 5 × 7.5 = 30,000 gallons.

Step 2: Determine Turnover Rate

Now think about how long it should take to move all that water through the filter once. This is called a turnover.

One full turnover a day is enough for most pools. Let’s say you want it done in 8 hours. Divide your total gallons by 8.

Example:

30,000 ÷ 8 = 3,750 gallons per hour

If you want to clean all the water in 8 hours, that’s how fast your pump needs to move the water.

Step 3: Look at Pump Speed

Now look at your pump. It may have a sticker or tag indicating its water flow rate. You’ll usually see gallons per minute (GPM).

To find gallons per hour, just take that number and multiply by 60.

Example: If your pump says 50 gallons per minute:

50 × 60 = 3,000 gallons per hour

Step 4: Find Pump Time

Here's how to calculate the pool pump run time. Find out how much water is in your pool. Then divide that by how much water your pump moves in one hour.

Example: 30,000 ÷ 3,000 = 10 hours

If you wonder how long to run a pool pump, 10 hours of operation will give this pool and pump a single complete cleaning.

Step 5: Adjust for Variables

Some days, your pool might need more time. Like when it’s very hot, or lots of people swim, or there’s dirt or leaves floating in it.

Other times, you may not need as much.

If you use a robot cleaner to pick up debris, your pump doesn’t have to work as hard. That could mean shorter run times and less energy used.

Tips to Optimize Pump Efficiency 

• Run the pump at night or early in the morning
• Use a timer so you don’t forget
• Keep the filters and baskets clean
• If you have an older pump, think about getting one that uses less power
• Use a robot pool cleaner to help out. A good robot cleaner can save time. It works on its own and helps your pool stay clean.

Common Mistakes to Avoid

Many pool owners make costly mistakes when running their pool pumps. A common error is running the pump for too long, which wastes energy, increases electricity bills, and shortens the pump’s lifespan. 

Another mistake is not considering the pool size or the pump’s capacity. Setting incorrect run times can lead to poor water cleaning or unnecessary energy use. Always base your schedule on your pool volume and pump speed.

Neglecting regular maintenance is also an issue. Dirty filters and worn-out equipment reduce efficiency and can cause breakdowns. 

Additionally, relying solely on the pump for cleaning can make it work harder than needed. Using a robot pool cleaner, like the Dreame Z1 Pro, can help ease this burden.

Avoiding these mistakes will save energy and keep your pool clean and enjoyable all season long.

Conclusion

You don’t have to guess when it comes to your swimming pool pump. Just find out how big your pool is, check your pump, and do a little math. Then you’ll know how many hours it needs to run.

You may run it more if your pool gets heavily used, or it draws more dirt. But if you own a robot cleaner, you can operate it less.

Pool care doesn’t have to be hard. Just take it one step at a time.