CSI vs LSI

beautifulpool

Well-known member
Jun 2, 2019
115
North TX
-0.07 CSI is fine.

CSI needs to be out of range for months to do damage to the surface. Short times out of range as chemicals drift is not a problem. Just correct levels to bring CSI back negative.
does knowing the difference between CSI vs LSI matter for a residential pool owner/operator/me? also, and not related, is it ok to add cal-hyp powder and LC on same day....a few hours apart?(why would i?, well idk, just kinda thought because i wouldnt mind increasing my 175 ppm CH, (yeah i know calcium can be added separately, but figured by the time that 20 lbs of calcium hypo sitting in garage gets in pool (i add a few PPM chlorine each evening depending on chlorine demand) but since i like the glisten of LC, and have both handy in garage.... figured if im increasing FC 4 ppm, why not give each type sanitizer some play....yes, im new to this...but whats wrong with increasing calcium and getting some glisten....another question....not related, k, so in balancing alkalinity, do most subtract 1/3 of CYA to determine TA, (i do it but doesnt make sense to me) and since CYA and i have had a bad pool history together, when the pool store assures me there isnt any CYA in natural chemistry's 'Pool Perfect', and i no longer use pucks nor Di-chlor, is it coincidental my CYA of 40 inches up slightly after each weekly dose of 'Pool Perfect'...i know many pool owners like their CYA, just hearing CYA makes me shudder.....
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
11,313
Northern NJ
does knowing the difference between CSI vs LSI matter for a residential pool owner/operator/me?
Calcium Saturation Index (CSI) - Trouble Free Pool is what we use here. Our guidelines and PoolMath tools make any necessary adjustments so you don't need to.

also, and not related, is it ok to add cal-hyp powder and LC on same day....a few hours apart?(why would i?, well idk, just kinda thought because i wouldnt mind increasing my 175 ppm CH, (yeah i know calcium can be added separately, but figured by the time that 20 lbs of calcium hypo sitting in garage gets in pool (i add a few PPM chlorine each evening depending on chlorine demand) but since i like the glisten of LC, and have both handy in garage.... figured if im increasing FC 4 ppm, why not give each type sanitizer some play....yes, im new to this...but whats wrong with increasing calcium and getting some glisten....
Yes. Fine to use Cal-Hypo to get to the CH target.

another question....not related, k, so in balancing alkalinity, do most subtract 1/3 of CYA to determine TA, (i do it but doesnt make sense to me) and since CYA and i have had a bad pool history together,
Our guidelines and PoolMath tools make any necessary adjustments so you don't need to.

when the pool store assures me there isnt any CYA in natural chemistry's 'Pool Perfect', and i no longer use pucks nor Di-chlor, is it coincidental my CYA of 40 inches up slightly after each weekly dose of 'Pool Perfect'...i know many pool owners like their CYA, just hearing CYA makes me shudder.....
We don't recommend the use of any pool store potions in the TFPC Methods.
 
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poolnoobgrandma

Well-known member
Sep 15, 2018
222
Seminole, FL
I would think that the deep end would be the place to ask the question of the difference between LSI and CSI.. I understand that Pool Math etc., do all the math, but ... again, this is the deep end subforum. I came to this thread via a search, because was curious about the same thing. I am trying to better understand the relationship between the various chemical levels and the balance of the pool water.

"WE PROVIDE
a forum where pool owners can learn, develop, and share their pool/spa knowledge."

If I were having trouble, I get the "follow the method" advice. But if I want to understand the method better, isn't this forum the place to ask?
 

Leebo

Admin
TFP Expert
LifeTime Supporter
Jul 21, 2011
9,079
Eastern Ohio
@poolnoobgrandma

I’d like to instead bounce you to this in depth discussion,

I hope you enjoy!
 

poolnoobgrandma

Well-known member
Sep 15, 2018
222
Seminole, FL
@poolnoobgrandma

I’d like to instead bounce you to this in depth discussion,

I hope you enjoy!
Thanks!