Southern folk... How long are you having to run your SWG to keep up with the long hot days and warmer pool temps?


Gold Supporter
Sep 15, 2018
Seminole, FL
This is my first time coming from spring to summer with our pool. Last year we took over at the summer's hottest and longest days and chlorine demand went down from there. We're keeping a cover on the pool when we're not swimming to keep it at 88 degrees. We take the cover off every day because we're swimming everyday. I'm just having a hard time getting to a point where the SWG is keeping up. Pool has been clear with no CC's but the chlorine has dropped from time to time below where I like it. And then the SWG has a hard time bringing it back up so I end up adding chlorine. Everything's good. Let it drift back down. Then rinse and repeat. How long do you run your pump and SWG in the summer?


Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
Bedford, TX

I suggest you keep a little Liquid Chlorine on hand to bring your FC up if it gets too low.

What is your CYA?? It makes a big difference in FC demand..

I keep my FC at my target or slightly above.. I never try to keep my FC between the minimum and my target.. I view my minimum as a cliff I never want to fall off, so I stay well away from it.

I have a 17K pool that runs 24/7.. In the middle of the summer I often have to run at 50 to 60% output on my 40K cell, to maintain my target.


Jim R.


Gold Supporter
Bronze Supporter
Nov 30, 2019
Pawleys Island, SC
No cover, heated to 88 degrees, FC maintained at 6 - 8 or so, pump/salt cell runs 15.75 hours/day at 10%. The pump run time was determined by our desired heat pump run time. We're two adults using the pool pretty much daily, no kids.


Gold Supporter
Jul 17, 2016
I have an Above Ground pool that stays uncovered year round. My SWG is rated for 40K gallons like yours. I run my two speed pump and SWG 24/7 at low speed with a setting of 25% output (3.1 ppm) for water temps up to 85 degrees. From 85 to 90 degrees, I run my SWG at 30% output (3.7 ppm). Finally for the heat of the summer, I run at 35% output (4.3 ppm).

I discovered these settings by graphing it out in EXCEL so that I can anticipate when to adjust my SWG. By learning my pool's tendencies, it makes my life much easier since I can test when I want and otherwise be worry free. I always try to keep my chlorine level at the higher side so that I do not have to worry about swim load or weather.

Good luck on learning how long to run the pump and the SWG. However once you get it down, it is very easy to maintain after that. Being in Florida, your electricity should be fairly cheap. Since you have a two speed pump like mine, you may want to just leave the cover off the pool and run your pump on low 24/7. Then you can just concentrate on the settings for your SWG which should alleviate any problems with keeping the chlorine stable.


Well-known member
Mar 11, 2015
SE Virginia
Pool Size
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
I checked my records during the peak last summer; 20k gal pool, 40k T-15 cell, 50-53%, 12hr pump runtime, CYA 70-80, no cover used, no problem with SWCG keeping up with demand.


Gold Supporter
Sep 15, 2018
Seminole, FL
Thanks for all the words of wisdom! I finally dialed it up to where the FC was increasing. So I dialed back the SWG a little. I also retested the CYA, and it was somewhere between 30 and 50 depending on whether you trust my eyes or my husband's eyes. Have I mentioned that I hate that test!? Either way, we can use a little more so I added a couple of pounds. Hopefully things will level out and I can keep it on the straight and narrow.


Bronze Supporter
Feb 5, 2018
Rogers, AR
There seems to be a big difference once cya passes 50...but you don't want to overshoot and get it too high. Try to gradually creep up on 70 and you will most likely notice your chlorine won't drop as much in a 24 hour period. As far as the actual test, it is the most difficult but you will get more confidence over time.


Gold Supporter
Bronze Supporter
Oct 25, 2017
Ocala, FL
Im a bit north from you, and I have a pool cage, but at this time Im finding running my SWG at 50% for 12 hours is holding pretty steady; actually adding a tiny bit over usage. I tested today and my FC is 7.5, up from 6.0 about 8 days ago. I suspect we still arent up to maximum FC usage yet here in Florida. Im happy with my FC being a bit on the high side for now.


Gold Supporter
Bronze Supporter
Jun 29, 2016
Tampa, FL
Hey there, neighbor! I like to keep my CYA around 70, which is appropriate for a salt water pool. Then I can run my salt cell for about 5 hours on super hot days, and it keeps up.


Silver Supporter
Aug 22, 2017
West Palm Beach/Florida
16K gallon pool. Run the SWG at 40% for 7 hours a day. Pool mainly uncovered, but the solar cover stays on all day sometimes. My CYA is at 70 and I keep FC around 8. When it dips a little I bump with LC. Pool is between 85 and 90 degrees now on most days.

Pay a lot of attention to CYA this time of year. Between the washout due to rain, and the high heat of the pool, CYA tends to degrade quite a bit. I find myself adding some at least once a month. Keep your CYA between 70 and 80 and FC at 10% of that and you are golden.


Mod Squad
LifeTime Supporter
Jan 17, 2012
Evans, Georgia
Grandma, I Just want to remind you that if you have kidlets in there swimming some days when you later find your FC lowered those darlings may have left some pee in the pool. Or possibly poor wipers. You get the idea, Im sure.

LUCKILY you catch those drops in FC and can boost your FC up quickly.keep

Just gotta be flexible.....and keep that test kit handy.



Gold Supporter
Sep 15, 2018
Seminole, FL
Thanks all!!! I raised the FC levels to where the SWG was keeping up. Added CYA (waiting for delivery of reagent so that I can test) and have started SLOWLY cutting down on chlorine generation to get back to recommended levels.