LSI calculation

[jmcmd1980]

My LSI:

Water temp 89
pH -I try to keep at 8.2
TA 65
Calcium 250
CYA 80
Salt 3500
Cl 2.5

LSI= .03

I have to add muriatic acid every day to keep the pH at a point to which gives a favorable LSI. Are there any other factors I could adjust so as not to have to keep adding the muriatic acid?

 

[cdadams1223]

Don't keep your pH above 8. Your TA is good and will eventually reach equilibrium with your pH. When your pH hits 8, reduce it with MA back to 7.2 - 7.5. You're FC level is very very low for a CYA of 80. See FC/CYA Levels to help you with what your FC level should be. CH seems a bit low for a plaster pool. Salt levels look good. What is the total volume in gallons of your pool? The pros will chime in soon with their thoughts.

Be sure to check these out as well!
Pool Care Basics
PoolMath

 

[YippeeSkippy]

CSI and LSI - Further Reading

www.troublefreepool.com

Please reads that and understand we don't follow LSI. Your pool is brand new, right? New pools are phenomenally labile when it comes to pH. You'll be adding it off and on for months to come as the plaster cures.

Plaster Start-Up Guides - Further Reading

www.troublefreepool.com

Plaster Installation and Maintenance - Further Reading

 

[YippeeSkippy]

Did your builder add salt already?? Are you using the SWG??
You should be using liquid chlorine at this point and more of it as your quite low as mentioned above.
FC/CYA Levels

 

[jmcmd1980]

Don't keep your pH above 8. Your TA is good and will eventually reach equilibrium with your pH. When your pH hits 8, reduce it with MA back to 7.2 - 7.5. You're FC level is very very low for a CYA of 80. See FC/CYA Levels to help you with what your FC level should be. CH seems a bit low for a plaster pool. Salt levels look good. What is the total volume in gallons of your pool? The pros will chime in soon with their thoughts.

Be sure to check these out as well!
Pool Care Basics
PoolMath

Thanks for your reply, pool volume by my calculation is about 14,000 gallons Including the hot tub and the sun shelf. Do you think I should bring up the hardness a bit? It’s below what the Jandy SWG documentation recommends. From my reading, I thought if LSI was OK you could stick with your numbers but I am very new with this
Jim.

 

[jmcmd1980]

Did your builder add salt already?? Are you using the SWG??
You should be using liquid chlorine at this point and more of it as your quite low as mentioned above.
FC/CYA Levels

My pool is 4-5 weeks old, saltwater was added about two weeks ago by the pool builder.

 

[jmcmd1980]

I just checked again.

Water temperature 98
FC 4
PH 8
TA 60
CH 260
CYA 65
SALT 3800

 

[YippeeSkippy]

Pardon my confusion- your signature line says the pool was filled July 8th. Did you mean June 8th?

Consider your CYA as 70- this isn't a linear scale, its logarithmic. So there is variance between each line. So any time you see its above one value, you have to consider it up at the next value.
Use some Muriatic acid to lower the pH.

Increase your SWG to keep your FC between 5-8ppm, with 3ppm being the least you ever want to drop to after swimmers and sun burn off.

Do you have any fountains or spill over on the spa? When they are running they are increasing your pH. Limit their use to a short daily flow so they remain refreshed with chlorine, but don't run continuously.

Maddie

 

[jmcmd1980]

I just checked again.

Water temperature 98
FC 4
PH 8

Pardon my confusion- your signature line says the pool was filled July 8th. Did you mean June 8th?

Consider your CYA as 70- this isn't a linear scale, its logarithmic. So there is variance between each line. So any time you see its above one value, you have to consider it up at the next value.
Use some Muriatic acid to lower the pH.

Increase your SWG to keep your FC between 5-8ppm, with 3ppm being the least you ever want to drop to after swimmers and sun burn off.

Do you have any fountains or spill over on the spa? When they are running they are increasing your pH. Limit their use to a short daily flow so they remain refreshed with chlorine, but don't run continuously.

Maddie

thanks,

My pool was filled June 8 not July 8. The pool company that installed the pool set the SWG at 85% and it is still at that level. I just tested, and my free chlorine was 4.0. I have a spa and sun shelf, and the spa is a champagne spa so it does spill over , but it is not on much.

TA 60
CH 260
CYA 65
SALT 30

 

[cdadams1223]

I just checked again.

Water temperature 98
FC 4
PH 8

thanks,

My pool was filled June 8 not July 8. The pool company that installed the pool set the SWG at 85% and it is still at that level. I just tested, and my free chlorine was 4.0. I have a spa and sun shelf, and the spa is a champagne spa so it does spill over , but it is not on much.

TA 60
CH 260
CYA 65
SALT 30

I think you might have a typo on your salt. Surely the last test wasn't 30ppm right? Maybe you meant 3000 something? It was 3500 at 10am and 3800 at 3:46pm this afternoon. Are you sure you're reading your test correctly? The color is a solid salmon color and pretty unmistakable.

Your CYA cannot be 65. CYA is on a logarithmic scale so round up to 70. With a SWG and your CYA at 70, your FC should be between 5-10 ppm with an absolute minimum of 3ppm. If you get close to 3, you're asking for trouble in the way of algae. Personally, I'd keep my FC levels at 9-10, especially in that Florida sun.

Remember, when your pH exceeds 8 you need to knock it down with muriatic acid (MA) back into the 7s, aim for 7.6 or so.

For a plaster pool, you should probably keep your CH a little higher than 260. Make sure you double check what
PoolMath says based on your pool parameters.

 

[jmcmd1980]

I think you might have a typo on your salt. Surely the last test wasn't 30ppm right? Maybe you meant 3000 something? It was 3500 at 10am and 3800 at 3:46pm this afternoon. Are you sure you're reading your test correctly? The color is a solid salmon color and pretty unmistakable.

Your CYA cannot be 65. CYA is on a logarithmic scale so round up to 70. With a SWG and your CYA at 70, your FC should be between 5-10 ppm with an absolute minimum of 3ppm. If you get close to 3, you're asking for trouble in the way of algae. Personally, I'd keep my FC levels at 9-10, especially in that Florida sun.

Remember, when your pH exceeds 8 you need to knock it down with muriatic acid (MA) back into the 7s, aim for 7.6 or so.

For a plaster pool, you should probably keep your CH a little higher than 260. Make sure you double check what
PoolMath says based on your pool parameters.

Thanks for your reply. Yes, my salt level on the SWG display reads 3900 or 4000, by Taylor test, salt is 3800. SWG generation set to 85%. Do I raise to 90% or higher to raise FC, or add some liquid chlorine?

I can add some calcium to boost CH to perhaps 300?

Thanks again,

Jim

 

[wireform]

You need to raise it by either upping the percentage or the pump run time or a combination of the two. Although not mentioned in your signature what pump do you have. I'd assume it's a Jandy vsp so then I would suggest running the pump 24/7 on the lowest speed the SWCG and or the heater requires to run and then add 100 rpm to that speed then you'd only need to adjust the percentage for the SWCG for the FC you're looking to achieve.

 

[ajw22]

CH of 260 is fine. There is no reason to raise it to 300. Let it be and monitor it. Your water is less than a month old. CH will accumulate and naturally rise.

All of your numbers look fine but you can run your FC a bit higher. Just add 2 to 3 ppm of liquid chlorine if you have it.

Focus on your FC and pH. Those are the two important tests to be constantly monitoring and adjusting in a new pool as things settle down.

 

[jmcmd1980]

Thanks very much, will do.

Jim

 

[mgtfp]

Are you using PoolMath to calculate the saturation index?

 

[jmcmd1980]

You need to raise it by either upping the percentage or the pump run time or a combination of the two. Although not mentioned in your signature what pump do you have. I'd assume it's a Jandy vsp so then I would suggest running the pump 24/7 on the lowest speed the SWCG and or the heater requires to run and then add 100 rpm to that speed then you'd only need to adjust the percentage for the SWCG for the FC you're looking to achieve.

Thanks for the reply. I updated my signature to include my Jandy EPUMP variable speed, and my Jandy CS200 filter, SWG Jandy PLC 1400. The pool installation company left me "high and dry" after the first few weeks of "caring" for the pool water when I did not agree to the $145/month service plan. I have not learned about adjusting the pump yet, they gave very little in the way of instruction.
I am going on vacation later this month for a week. Should I set the pump and SWG differently while away, put in liquid chlorine and muriatic prior to departure?


Thanks again, Jim

 

[jmcmd1980]

Are you using PoolMath to calculate the saturation index?

Thanks for the reply. I use the Orenda calculation and got LSI 0.01 with numbers:

Temp 88
pH 8.2
TA 60
Calcium 260
CYA 70
salt 3800
FC 4

LSI is good by calculation, but pH is high, I add acid daily to reduce it but it doesn't last. Any advice greatly appreciated.

Jim

 

[mgtfp]

All our recommendations in regards to saturation index are based on PoolMath. You can't really mix TFP with other methods.

 

[jmcmd1980]

I will switch to the Pool Math calculator and see what I get

Jim

 

[jmcmd1980]

All our recommendations in regards to saturation index are based on PoolMath. You can't really mix TFP with other methods.

I plugged in my latest numbers and CSI 0.09.

Jim