Chemicals off

We are new owners to a 33,000 gallon gunite salt water pool and are trying to do or own maintence. We struggled with trusting pool builders so I'm not suprised our first reading is way off. Our pool company just finished "maintaining" levels for us for the past month. I checked our levels today with the TF-100 kit. PH 8.2, no chlorine, TA 40, CYA ? None?, CH 225. Our SWG says low salt. The pool looks fine. I have everything in the pool math app. I guess I'm wondering where to start as far as adding chemicals. Thank you so much in advance!
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
21,157
Bedford, TX
Jess,

The first thing you have to do is get your FC up.. Your SWCG is made to maintain your FC, but to add FC quickly you need to use Liquid Chlorine.. I'd add enough liquid chlorine to get your FC up to 5 ppm...

Without CYA the sun will eat almost all the chlorine that your SWCG produces. Please confirm that with the CYA test, the dot never went away... If so, I would add enough CYA (stabilizer) to get your CYA up to 50. Once stabilized you can then slowly move up to 70 or so.

Tell us about your pool by completing your pool's signature.. You can use mine as an example.

How big a SWCG do you have, and how long do you run your pump each day???

I'd also add a little muriatic acid (MA) to lower your pH from 8.2 to 7.7 or so.. SWCG pools like their pH about 7.8.

Thanks,

Jim R.
 

HermanTX

Gold Supporter
May 20, 2020
1,530
Katy TX
Pool Size
14600
Surface
Plaster
Chlorine
Liquid Chlorine
Jess,

The first thing you have to do is get your FC up.. Your SWCG is made to maintain your FC, but to add FC quickly you need to use Liquid Chlorine.. I'd add enough liquid chlorine to get your FC up to 5 ppm...

Without CYA the sun will eat almost all the chlorine that your SWCG produces. Please confirm that with the CYA test, the dot never went away... If so, I would add enough CYA (stabilizer) to get your CYA up to 50. Once stabilized you can then slowly move up to 70 or so.

Tell us about your pool by completing your pool's signature.. You can use mine as an example.

How big a SWCG do you have, and how long do you run your pump each day???

I'd also add a little muriatic acid (MA) to lower your pH from 8.2 to 7.7 or so.. SWCG pools like their pH about 7.8.

Thanks,

Jim R.
Yes, with the CYA test the dot never went away. I added all of the above so I will update you tomorrow. Thank you! They set it for us to run from 9 am - 6 pm everyday. We have a 1.5 HP Variable speed pump that runs the pool circulation and deck jets and another 1.5 HP Variable speed pump that runs the spa (waterfall) and bubblers on the tanning ledge. We haven't yet figured out a schedule for the pumps yet.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
21,157
Bedford, TX
Jess,

Well, your cell is way too small for your pool.. We always recommend a cell that is 2 x the volume of the pool... That said, it will work, but you will need to run a lot longer than 9 hours a day

Do you know what output % your cell is set for??? No matter where it is set now, you need to set it at 100% and maybe we can reduce it later..

An IC40 in your 33K pool, will produce a total of 5.1 ppm of FC per day with the cell running at 100% That is .21 ppm of FC per hour

A normal pool used between 2 and 4 ppm of FC per day.. So, let's go with 3 ppm of FC usage per day.. 3/.21 is 14.. that means even at 100% output you will have to run your pump for 14 hours...

The fact that you are only running the pump for 9 hours, and I suspect the cell is set to something like 50%, is why you have no chlorine in your pool..

I would test your FC at the same time for several days and see what the trend is.. If the FC is going up, then you can reduce the run time or the output %.. If the FC is going down you will need to increase your run time or increase the output %.. (Unless you are already at 100%)

If you try to adjust your FC every day, it will drive you crazy, as your pool uses a little more or a little less FC each day depending on the weather and pool usage.. So this is what I do...

I try to keep my FC at my "target" or higher.. I do not try to keep my FC between my minimum and my target.. I look at the minimum as a cliff I never want to get close too. This means if it is cloudy, for a day or two and my FC goes up a little, I don't care, as it will soon get sunny and the FC will come down. Doing this means that I don't have to adjust the SWCG output but once a month or less.

See the saltwater section of this chart for reference.. FC/CYA Chart

Thanks,

Jim R.
 
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mguzzy

Gold Supporter
Hi Jess.. we will figure this out.. to add to what Jim said, and I know thats a lot to digest.. we need to figure out your salinity too. You should order a k1766 test kit from the same place you got the TF100.. until it comes in maybe run a sample to the pool store for a quick guess. Your swg shouldn't be complaining about low salt.
 
Thank you all. I did what Jim had recommended last night and this morning FC: 3, no CC, CYA 25, TA 40. I actually pulled out the pH probe thing I bought because ph was still reading high and it was 9.3 so I added more muriatic acid and a little more liquid chlorine this morning. We also figured out how to find the actual salt level and it was 2300 so we added 4 bags of salt. This evening FC 2.5, 0.5 CC, CYA 35, TA 40, CH 375. I think it's set at 60% and now says good for salt level at 2900. I will turn it up to 100%. I'll order the other test kit as well. I figured we would need to run the pump more. They told us no but also told us we only needed a 0.75 hsp single speed pump and we insisted on a bigger VSP. Thank you for all your help so far. I told my husband I could do it and it wouldn't be alot,of time each week so I'm hoping to get it figured
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
2,087
Spring Valley, NY
So that you know cya of 25 is 30 and 35 is 40. Which one is correct assuming you didn't add an stabilizer. To be safe call it 40.
Don't add more salt until you get the K-1766 salinity test kit. As long as the cell isn't showing low salt for the time being let it be.
Your FC is too low. Target for 40 CYA is 5-7. Bring it up to level with liquid chlorine and maintain it from there out with the SWCG.
 
Jess,

Well, your cell is way too small for your pool.. We always recommend a cell that is 2 x the volume of the pool... That said, it will work, but you will need to run a lot longer than 9 hours a day

Do you know what output % your cell is set for??? No matter where it is set now, you need to set it at 100% and maybe we can reduce it later..

An IC40 in your 33K pool, will produce a total of 5.1 ppm of FC per day with the cell running at 100% That is .21 ppm of FC per hour

A normal pool used between 2 and 4 ppm of FC per day.. So, let's go with 3 ppm of FC usage per day.. 3/.21 is 14.. that means even at 100% output you will have to run your pump for 14 hours...

The fact that you are only running the pump for 9 hours, and I suspect the cell is set to something like 50%, is why you have no chlorine in your pool..

I would test your FC at the same time for several days and see what the trend is.. If the FC is going up, then you can reduce the run time or the output %.. If the FC is going down you will need to increase your run time or increase the output %.. (Unless you are already at 100%)

If you try to adjust your FC every day, it will drive you crazy, as your pool uses a little more or a little less FC each day depending on the weather and pool usage.. So this is what I do...

I try to keep my FC at my "target" or higher.. I do not try to keep my FC between my minimum and my target.. I look at the minimum as a cliff I never want to get close too. This means if it is cloudy, for a day or two and my FC goes up a little, I don't care, as it will soon get sunny and the FC will come down. Doing this means that I don't have to adjust the SWCG output but once a month or less.

See the saltwater section of this chart for reference.. FC/CYA Chart

Thanks,

Jim R.
Thanks Jim. I turned it up and ran the pump 13 hours and yesterday FC was up to 4, CC 0.5; today FC was up to 6.5, CC 1.0. The ph is staying high. It was back up to 8.6 today. I'm waiting on the salinty kit.
 

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Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
21,157
Bedford, TX
Jess,

I suggest that you try to keep the pH somewhere in the 7's.. Once it gets above 8, you want to add some 31% Muriatic acid...

Pool math can tell you how much..

To lower your pH from 8.6 to say 7.6 will take about 128 oz. of MA.. I kind of doubt your pH is really 8.6, so I would add 48 oz. and retest in an hour and see what effect that has on your pH.. If still not in the 7's, I'd add another 48 oz. etc..

If your cell is working, no red lights, then your salt level has to be somewhere between 2600 and 4000.. So the world is not going to end while you wait on the salt test kit.

Thanks,

Jim R.