How long to run filter on daily basis

curt222

LifeTime Supporter
Jun 4, 2008
8
#1
I did a quick search, but didn't see this question on the board. I just purchased a 15x30 above ground pool with a two-speed sand filter. The guy at the pool store suggested that I run the filter on low speed, 24 hours a day. He said it would use less electricity and work better. I'd appreciate any thoughts on whether this is the optimal way to run my filter or if I should run it on a more limited basis.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#2
Welcome to TFP!

That is good advice. With a two speed pump you want to run it on low speed most of the time to save electricity. Some people like to bump it up to high speed for half an hour to help the skimmer work more effectively, others don't have any problems with skimming.

On low speed a 24 run time is a good starting point. You may not actually need that much run time, depending on the relative size of the pump and the pool. Try it on 24 hours for a couple of weeks and get a sense of what the water looks like. Then cut it back to say 20 hours for a week and see how the water looks then. If everything still looks excellent then you might want to try an even shorter run time. Just keep in mind that you often need a longer run time when the water is warm and a shorter run time when the water is cold.
 

crokett

Well-known member
Jul 17, 2007
535
Hillsborough, NC
#3
JasonLion said:
Welcome to TFP!

That is good advice. With a two speed pump you want to run it on low speed most of the time to save electricity. Some Just keep in mind that you often need a longer run time when the water is warm and a shorter run time when the water is cold.
Interesting. Why? do the nasties not grow as well in cold water so therefore less filtering needed? Less swimming goes on in cold so less need for circulation or do you get better circulation in cold?

I was told run it at least long enough to turn your water over once. I have a 1000GPH pump and ~3300 gallons in my pool so I run it 4 hrs from 9pm to 1am. After this forum helped me clean up the algae bloom last year I had no problems doing it that way. If I am adding chemicals I adjust the start/top times on the timer accordingly.
 

Rangerman

LifeTime Supporter
May 28, 2007
220
Fayetteville, Arkansas
#4
I don't know that it's necessarily best or not, but I run mine 24/7 throughout the season. Thinking about shutting it down at say 10pm and restart at 6am. I usually add bleach around dusk (8:20ish). I would think it would have time to mix before shut down. Agree?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#5
One turnover per day is an approximation of the actual requirement, which is to keep the pool clear and sparkling. The actual time required varies with several factors, most significantly water temperature and bather load. The amount of debris falling into the pool is also significant in some areas. Water temperature enters in because chemical reactions and biological growth rates both vary with temperature.

Figuring out the actual flow rate is tricky. You can't just use the pump specification since the actual flow rate depends on many details of your plumbing. Because of that it is often simpler to go straight to an empirical test, ie look at the water and see what it looks like. If the water is perfect you can try a shorter run time, if it looks dull then try a longer run time.