Startup SWG chlorinator salt for new pool

Jump to latest Follow Reply
ok i tested salt today for the first time and its 3200 ppm, my SWG chlorinator runs 3000 to 4000, so i started it up today for the first time to test its all ok, and i changed my pool math app to SWG, i am having trouble getting my CYA level confirmed but think its 50, i put 50 into pool math and understand now as its running on the SWG the FC level needed is lower, pool math recommends 3 with cya 50,

i see i need to raise CYA to at least 70 going by the chart, but i need to confirm cya level before adding more , i am looking into it now my testing isn't working correctly, i am waiting on a new test i ordered

as for SWG chlorinator i was not sure on where to set output and time but my guess is 7 hours overnight, running at maximum output, 7 days a week, so its set to start tonight for the first time , i tested FC at this point its 5.8 which is high for 50 cya

i assume i should run SWG chlorinator every night when i run filter, and eventually work out what output and time is needed to keep FC at correct level

i guess i try for CYA 70 FC 5 as chart says but first i got to sort out the cya level pool is at..... how am i doing here ?
 
I'd say stick to the target-range of the non-SWG chart until you are dialed in and have worked out the exact CYA with the new reference sample that Brett is sending. That also gives you a bit more margin for error should something go pear-shaped.

Regarding SWG settings: I just looked up your RP9 cell: It has a chlorine production of 30g/h at 100%, which is equivalent to 1.58lbs/day. You then go into PoolMath's "Effects of Adding", enter your "Pool Volume" (36000 L) and pick "SWG" in the "Chemical Additions" drop-down. Then tap the search magnifying glass next to "24 Hour SWG Output" and pick a cell. Your exact cell doesn't seem to be in the list, but you can pick the Watermaid EZ300, that seems to have the same output of 1.58lbs/day. Then you can set the "SWG%" and the "Pump Run Time" and PoolMath will tell how much FC will be produced with these setting. E.g., 3 hours at 100% will increase your FC by 2.5ppm.

Now go through your bleach additions over the last weeks and work out with PoolMath what your average daily FC additions with bleach were to keep your FC constant. Then find the correlating "SWG %" to produce the required FC during your pump run time. Something like 30%-50% and a pump run time of 4-6 hours will probably be right for now in early spring.

Should your FC drop below min, then it's easier to correct with a bit of bleach and put the SWG up a notch, rather than cranking the SWG up to get back to target and then dial it back again to maintain FC. The SWG is great for the regular FC additions. To get up a step (e.g. when changing target range after increasing CYA) is usually easier by adding a bit of bleach rather than fiddling round with the SWG. At least until you worked it all out, and you probably still have a bit of bleach hanging around that you don't want to go off.
 
  • Like
Reactions: FIESTA62 and Dirk
no solar, i might get around to that later but for now i have off peak rates from 10pm to 7am, my pump is variable speed, i have it on Eco mode which is 1900 rpm, i think from memory thats 150 LPM, i have a water metre on the system showing LPM, the chlorinator is running fine with that slower speed, Watermaid told me the RP9 can run as slow as 100 LPM, so i figure with off peak rates and running Eco mode power costs should be low...
 
I'd make sure to have some overlap with times when you are at home and awake to see if everything is working as planned. Great reassurance to actually see your cell bubbling away.
 
  • Like
Reactions: FIESTA62
62,

One thing that will help get used to a salt pool is don't over adjust the chlorinator. If you get to anal about it the thing will drive you nuts. it is okay to run a part per million or two higher then Target. So using pool math for your initial settings and start a little bit higher then predicted. Test your free chlorine each day to see if it is trending up or down. You will find the reading cycles somewhat depending on pool load and other factors. Try to avoid adjusting more than once a week. the idea is to get a cycle established that never drops below Target and then leave it there.drifting up a few parts above never hurts anything. I learned this technique from one of our experts (@Jimrahbe) and it really makes using the chlorinator very easy.I only have to adjust once or twice per year using this technique.

I hope this helps.

Chris
 
  • Like
Reactions: FIESTA62, Jimrahbe and mgtfp
Most excellent posts all! (#22 on). Really good info, and the OP now has a great head start to getting the SWG tuned in.

An SWG user should always have a few jugs of liquid chlorine on hand. Not only for adjusting the SWG, but also for goosing the FC as needed (like before and/or after a big pool party or a very hot set of days or some sort of chlorine hit, like a dead animal in the pool). As pointed out, best to maintain FC with an SWG, but move FC with liquid chlorine.
 
Last edited:
  • Like
Reactions: FIESTA62 and Dtkokay

Enjoying this content?

Support TFP with a donation.

Give Support
mgtfp said:
Something like 30%-50% and a pump run time of 4-6 hours
Click to expand...

i checked FC last night before swg started it was 5.8, i set at 100% for 7 hours overnight, watermaid suggested 100%, ok i test this morning and FC is 9 wow highest ever the swg kicks butt, so i obviously need to backoff the swg,

i will turn off cell for tonight to let FC drop back , as its 9 now i assume i dont need to produce any more , i will restart wednesday night from a lower FC level , i will check what it is so i know the base i am testing from, and will try 50% as you suggested and try 5 hours and see what that does
 
Last edited:
Yep, needs a bit adjusting. I would have expected even a bit more then an FC increase of 3.2ppm.

By the way: Are you testing with with a 25ml sample to get a test precision of 0.2?

In most cases it is sufficient to use a 10ml water sample. One drop of titrating reagent will then be 0.5ppm FC. With the 25ml sample and one drop per 0.2ppm you just burn through reagent with not much added benefit. Clear Choice Labs doesn't even mention the higher precision test with a 25ml sample in their instructions.
 
  • Like
Reactions: FIESTA62
mgtfp said:
Yep, needs a bit adjusting. I would have expected even a bit more then an FC increase of 3.2ppm.

By the way: Are you testing with with a 25ml sample to get a test precision of 0.2?

In most cases it is sufficient to use a 10ml water sample. One drop of titrating reagent will then be 0.5ppm FC. With the 25ml sample and one drop per 0.2ppm you just burn through reagent with not much added benefit. Clear Choice Labs doesn't even mention the higher precision test with a 25ml sample in their instructions.
Click to expand...
yep i been using 25ml, i thought while i am in the learner phase better to keep things accurate as possible, but if there isn't much difference worth worrying about i will try the 10ml test ...

i did the calculations on pool math as you described effects on adding, i see my 100% for 7 hours should have raised FC by 5.8, i got 3.2, but i understand its not going to always be 100% accurate but it gives a good guide, i will be doing that method any time the FC drops below target....
 
Sounds like you are having all kinds of fun with your new toy. I have never had very good luck "predicting" where my SWG should be by trying to calculate it ahead of time. That's not to say its not worth it to do the calculation at least once in your life, its good to know how these things work, theoretically. But I've found there are so many things that can affect your FC retention, and some change in the short term, some change in the long term, some you have control over, some you don't.. Like CYA level; your local environment where you are in the world and how much incident solar radiation you get, the seasons, bather load, temp, yadda yadda yadda. Its like trying to draw a vector diagram to go to the store, why make it more complicated that it needs to be.

So I take a more pragmatic approach. I set my SWG at 50% and test how much FC I get. I then change the pump runtime/SWG ontime to get me to where I want to be in FC ...more or less. Once I have that dialed in, in a general way, I have quite a bit of lee way to adjust up or down (50% up or down) to fit the immediate conditions. Its getting hot or we are going to have a pool party, Turn it up. It cooling off or its been overcast for three days, turn it down. I have found over the course of 2 cells that the Cl production output will vary with the age of the cell; production goes down as the cell ages, and production goes down when the cell needs attention; something is clogged in it or its developing scaling. So if I see abnormally low FC production I am prompted to check those things as well, besides an algae issue. In general I really only have to track two things, my current FC level/retention and the % production on the controller. If I need more Cl I turn the knob up, if I need less Cl I turn the knob down.

Hope that makes sense.
 
  • Like
Reactions: FIESTA62 and mgtfp
mguzzy said:
Sounds like you are having all kinds of fun with your new toy. I have never had very good luck "predicting" where my SWG should be by trying to calculate it ahead of time. That's not to say its not worth it to do the calculation at least once in your life, its good to know how these things work, theoretically. But I've found there are so many things that can affect your FC retention, and some change in the short term, some change in the long term, some you have control over, some you don't.. Like CYA level; your local environment where you are in the world and how much incident solar radiation you get, the seasons, bather load, temp, yadda yadda yadda. Its like trying to draw a vector diagram to go to the store, why make it more complicated that it needs to be.

So I take a more pragmatic approach. I set my SWG at 50% and test how much FC I get. I then change the pump runtime/SWG ontime to get me to where I want to be in FC ...more or less. Once I have that dialed in, in a general way, I have quite a bit of lee way to adjust up or down (50% up or down) to fit the immediate conditions. Its getting hot or we are going to have a pool party, Turn it up. It cooling off or its been overcast for three days, turn it down. I have found over the course of 2 cells that the Cl production output will vary with the age of the cell; production goes down as the cell ages, and production goes down when the cell needs attention; something is clogged in it or its developing scaling. So if I see abnormally low FC production I am prompted to check those things as well, besides an algae issue. In general I really only have to track two things, my current FC level/retention and the % production on the controller. If I need more Cl I turn the knob up, if I need less Cl I turn the knob down.

Hope that makes sense.
Click to expand...
yes makes sense i get it, adjust pump time to suit, i guess there is a minimum needed on pump time to filter pool , example 50 percent at 2 hour pump time might get FC to the level i need , but 2 hours pump would not be enough filter time, so its a bit of a juggle act get FC right with enough pump time to filter pool, but i get what your saying that makes it easy to have play up or down if its sitting at 50, i will try that
i like the calculation idea to get me in the zone rather than just guessing as i did, when target was 6 i tried 100% for 7 hours and went way over to 9ppm FC, so i use calc to get around the area then i can play with pump time....
just waiting on my cya test so i can confirm what FC target i am looking for....thanks
 
FIESTA62 said:
i like the calculation idea to get me in the zone rather than just guessing as i did, when target was 6 i tried 100% for 7 hours and went way over to 9ppm FC, so i use calc to get around the area then i can play with pump time....
just waiting on my cya test so i can confirm what FC target i am looking for....thanks
Click to expand...
After years of trial and error I used "the effects of adding" in that PoolApp to figure my runtime when I found this site. Turns out I was pretty close. The "target" you are shooting for is the FC according to the now famous FC/CYA Levels. Tweaking the knob gets you there. Sounds like you are well on your way!

So the weather is cooling in my hemisphere as is the angle of the sun on the pool, So I see my FC is going up with the same runtime.. I think I have my nob turned down to about 30% going into the fall. I think the smoke from all our fires as created and interesting situation with my pool. It definitely wasn't seeing as much direct sunlight. But then again all the ash created a different chemical experiment in the big gunite crucible.
 
I don't want to overwhelm you with instructions on top of what you've already got. But I will anyway! This is what I found works for me, and I believe is the quickest way to your SWG setting.

SWGs are great at maintaining FC, but not so great at moving it from one level to another. Use liquid chlorine (LC) for that. Here's how.

Determine your target FC level.
Determine what % and runtime you want to first try out for the SWG.
After running the pump for at least 30 minutes, test your FC. Record the time you do so.
If it is low, use LC to bring your FC to target level.
If it is high, do nothing.
Turn on the SWG.
The next day, at the same exact time (after running pump for 30 minutes again), test your FC.
If it is low, use LC to bring your FC to target level and increase the SWG production a notch.
(Either by turning up the % or by increasing the SWG runtime, or both.)
If it is high, decrease SWG production a notch.

Repeat that everyday, at the same time, until your FC holds the target level. Thats your SWG %/runtime setting.

The idea is to bring the FC to target each day, at the same time each day, using LC, rather than trying to do that with the SWG, so that you can tell quickly if the SWG is over- or under-producing over a 24 hour period. If you're using the SWG to raise FC, you'll have a lot longer battle, because your SWG setting will not be what you'll eventually want to know, that which will maintain FC, but rather at a setting that will raise FC.

Hope that makes sense. It's much easier to do than to explain.
 
Last edited:
  • Like
Reactions: FIESTA62
overwhelm me its all good more the better.... thanks for the ideas here, i am onto it, i got the cya test today and tried a few times to to be sure, i got 60 very very faint dot i mean i had to stare and really look hard to see a faint spot but it was like 90% gone.....went to 50 and dot is gone, but really 60 was so close hard to tell, thing is i know i put 2.8kg of stabilizer in so it should be 80, so makes me think its closer to 60 than 50,
so i see 60 needs 4 FC or 50 needs 3 FC, what would u all do , go with its pretty much gone at 60 and do 4 FC, or go with defiantly gone at 50 and do 3 FC , ?

attached a pic of pool its almost finished got to do a deck at 1 end but main area is done, water looking crystal clear thanks to all the help from you guys out there, put the heater on yesterday and its already up to 26 Celsius / 79 F first swim is coming up on the next sunny day, kids on holidays for 2 weeks

and will get the swg sorted soon....
 

Attachments

  • Tony pool.jpg
    Tony pool.jpg
    615.6 KB · Views: 30
  • Like
Reactions: mgtfp
FC 4

Pool looks fantastic!

No scratch that. Where did you get those numbers?

If the SWG is running, and you have CYA 60, then your target FC is 4. If you think you have CYA 80, then your FC target is 6.

But if you haven't turned the SWG on yet, then CYA 60 would be FC 7-9.

Here's the chart you should be using:

www.troublefreepool.com

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.
www.troublefreepool.com www.troublefreepool.com
 
Last edited:
  • Like
Reactions: FIESTA62

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply