I cant keep up chlorine production in my pool. 90+ degree temps in NYC the past week or so and i'm losing between 1-2ppm in the pool daily. Water is good, fc is 6, ph 7.4, cya 70 salt 3400ppm, ta is 100. Had a bout with yellow algae and slammed the pool, and did a oclt and lost 0.5 ppm. I'm running my pump for 8 hours a day and the salt generator is at 100%. I was considering adding more salt as it recommends salt levels between 3200-4000ppm and running the pump longer, maybe 10-12 hours (my electric bill is going to suck! lol). The only thing that sticks out is that your forum recommends a generator 2x the size of the pool, and not knowing this prior to purchasing the equipment last year, the generator is rated for 10k gallons. It's a generic brand sold as the pool supply comany's brand called SWG from Island Recreational. I'd like to find out what the output of the generator is as ppm/hr and what my chlorine loss is during the day. The pool is in full sun for approx 10 hours a day. Any help would be appreciated. Thanks again!
scratching my head for answers
- Thread starter goinflyn
- Start date
Have you got a manual which comes with the SWG- that will usually give you an output in grams/per hour at 100%.
If you can find that information you can then play around in Poolmath to see how much FC your adding per hour.
The easiest way to determine your approximate daily FC loss is to test first thing in the morning just before the sun comes up and once the sun goes down. This will of course be relative to the amount of sunlight your pool receives and swim load.
If you can find that information you can then play around in Poolmath to see how much FC your adding per hour.
The easiest way to determine your approximate daily FC loss is to test first thing in the morning just before the sun comes up and once the sun goes down. This will of course be relative to the amount of sunlight your pool receives and swim load.
I'm giving my opinion on this, as I'm still new to the SWG crew, but I have a feeling the pros will agree. Running your pump 8 hrs a day, you're only getting 1/3 of its potential output. Given that your pool volume comes out to 9300 gallons, and you've got a 10k value brand SWG, it will probably struggle to keep up running 24 hrs a day. A good way to figure out what to do would run the reverse OCLT. Wait until sunset, then test your FC. Turn the SWG to 100% and let it run all night. In the morning test your FC again. Assuming you test at 10pm then again at 6pm (8 hrs), that would be the total amount of chlorine you're adding a day with your current pump times. Unless you record 2-3 FC during that time, your SWG doesn't stand a chance at maintaining your FC levels during just an 8hr period.
You're going to figure that you'll lose 2-3 FC per sunny day with moderate pool use. You'll have to do a little math following your reverse OCLT to find out how many hrs/day that translates to.
You're going to figure that you'll lose 2-3 FC per sunny day with moderate pool use. You'll have to do a little math following your reverse OCLT to find out how many hrs/day that translates to.
I'm still working on dialing in my SWG/pump times, so I was playing around with numbers anyway this morning. Looking at different brands of SWGs it seems that they average a generous 0.4 lbs of chlorine per 10k gallons rated capacity. Also assuming that this is referring to the amount of trichlor and playing around with the PoolMath calculator it doesn't look good for your setup.
0.4 lbs equals 6.4 oz of trichlor per day if running at 100% for 24hrs. (All this is based on my new understanding of SWGs, I may be way off, still looking for a pro's corrections)
Anyhow, that equates to a dose of 4.7 FC per day. And if you're running your SWG at 100% for 8 hours, you'd get a 1/3 of that dose, or about 1.56 FC per day. Then at a 'normal useage' of 2-3 FC per day, you're losing 0.5-1.5 FC per day at your current pump times.
And that's at a generous .4 lbs per day, it appears the Pentair line of SWG's claim closer to 0.35 lbs per day. My lesser known brand suggests a little over 0.4 lbs per 10k per day.
But assuming I am doing the math correctly, this does seem to agree with your claim of losing 1-2 FC per day. So it would appear the answer would be to ramp up the pump time to around 15 hrs per day running the SWG at 100%, if you value less pump time per day. If you reduced the SWG to 75% it would seem you'd have to run the pump pretty much all day long to give a 3 FC per day dose. Barring the reverse OCLT, I'd suggest raising your pump time to 15 hrs per day and see if your FC usage doesn't flatten out.
0.4 lbs equals 6.4 oz of trichlor per day if running at 100% for 24hrs. (All this is based on my new understanding of SWGs, I may be way off, still looking for a pro's corrections)
Anyhow, that equates to a dose of 4.7 FC per day. And if you're running your SWG at 100% for 8 hours, you'd get a 1/3 of that dose, or about 1.56 FC per day. Then at a 'normal useage' of 2-3 FC per day, you're losing 0.5-1.5 FC per day at your current pump times.
And that's at a generous .4 lbs per day, it appears the Pentair line of SWG's claim closer to 0.35 lbs per day. My lesser known brand suggests a little over 0.4 lbs per 10k per day.
But assuming I am doing the math correctly, this does seem to agree with your claim of losing 1-2 FC per day. So it would appear the answer would be to ramp up the pump time to around 15 hrs per day running the SWG at 100%, if you value less pump time per day. If you reduced the SWG to 75% it would seem you'd have to run the pump pretty much all day long to give a 3 FC per day dose. Barring the reverse OCLT, I'd suggest raising your pump time to 15 hrs per day and see if your FC usage doesn't flatten out.
Double the run time for now and see if the FC stabilizes or increases. From there adjust the pump run time as needed.
Any recommendations for a properly sized swg based on my pool size? I’m running my pump from 7p to 7a tonight to see how much chlorine I have in the pool tomorrow morning. They should give me an idea on how to proceed. Do they make chlorine tablets without cya in them or just stick to liquid for the time being?
Checked the pool water this morning with a 12 hour run time at 100% and the fc increased from 4 to 6. So my SWG will generate 4ppm every 24 hours. That's not good. I lose at least 3ppm daily. I added liquid chlorine to the pool to bump up the fc to 9ppm to give me a buffer.
So i'm reading online that a 40k swg generates approx 1lb of chlorine every 24 hours, or 10ppm at 100%. Is the output of the SWG the same using either a VSP set to a low rpm or a single speed pump if the run time is the same, say 12 hours? Does pushing more water thru the SWG generate more chlorine? Thanks again
- May 3, 2014
- 61,604
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Depending on brand 40K rated SWCG's can create 1.25 to 1.40 lb of chlorine gas per day. How much FC that is depends on your pool size.
As long as the pump rate is sufficient to close the flow switch to run the SWCG it does not matter what the flow rate is through the SWCG.
As long as the pump rate is sufficient to close the flow switch to run the SWCG it does not matter what the flow rate is through the SWCG.
Great info!!!! I figure for this year I’ll keep my pump and upgrade the swg. I can run the pump for 8 hours and the 40k swg at 100% to generate approx 5ppm daily. Next season I’ll upgrade to a vsp and adjust accordingly. What do you think? Or should I get the vsp and run the pump slow for 16 hours and set the swg to 50%? Is it the same wear And tear on the swg? Thanks again.
There's no definite % setting that we can give you. It's all trial and error, and specific to your pool usage, and chlorine demand. Start at 50% and make your adjustments until it maintains your desired chlorine level. With the VSP, as long as your minimum flow rate still activates the salt system, you should be able to set the % at a lower setting, since it will be cycling the salt system on and off throughout the day, depending on the % setting. You should set your VSP on high and low, depending on gallons and filtering... and if you have an automatic pool cleaner. You just want to make sure you have enough high speed to filter and run your cleaner, then low speed the rest of the time.