CSI winter ?

iain42

0
Oct 16, 2016
367
Little Rock AR
I like to leave my pool open all year because if we can't swim we it is beautiful to look at... Instead of COVID having me at home work and life has had me neglecting my pool chemistry.

Since the SWG doesn't run due to cold I've added chlorine Pucks. The pucks should raise FC and CYA a bit.
FC 0.8
PH 7.4
TA 40
CH 320
CYA 30-40 hate the dot test lol...
SALT 3300
TEMP 47
CSI -1.06

I'm not exactly sure what is affecting CSI. In what order and what levels should I adjust first??

thanks
 
Let your pH drift up to around 8.0 to help get your CSI in range. I prefer that in the winter, instead of adding calcium that I will have to worry about causing scale when the water warms up.
 
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Your chlorine and CYA are low, but the pucks will help that. The pucks are also acidic and will keep your pH down, so if it takes too long for your pH to rise and get your CSI back in line, you could consider pulling the pucks and switching to liquid chlorine.
 
For years now, I have cautioned to keep CSI within perspective but that sure falls on a lot of deaf ears. My guess is I will go to my grave trying to convince some folks that CSI is more often than not irrelevant.

CSI is a very useful tool IF you have hard fill water. It's not totally that simple but it's reasonably close to that and if you do NOT have hard fill water, your CSI concerns are fairly useless What kind of fill water CH do you have out there in ole' Little Rock? I pulled this quote as one among many that was easily found with google.
" Arkansas has one of the lowest averages for hard water in the country at 38 PPM, according to the USGS water hardness measures, Some examples of soft water cities are Little Rock with 26 PPM and Fayetteville with a hardness level of 27 PPM. The hardest water level in the state comes from Pine Bluff, which gets its water from 4 wells that pump from the Sparta Sand Aquifer. "

Burn your time and energy with careful study of the FC/CYA relationship and how algae sneaks up on your pool in mid-summer often undetected.......those are important issues you will face......CSI is not with water like that.
 
I'm not exactly sure what is affecting CSI. In what order and what levels should I adjust first??
"42", I'd like to address your main question. PH and water temp have the biggest and most immediate impact on CSI. Your CH is fine, but your TA is a bit low. As noted above, I would let the pH rise to about 8.0, maybe even 8.2. Also increase the TA to about 60 for now and see how those two settle in a few days. As long as you keep the pH around 8.0, it will compensate for the cold water. In the spring, then you can keep the pH a little lower. Hope that helps.
 
For years now, I have cautioned to keep CSI within perspective but that sure falls on a lot of deaf ears. My guess is I will go to my grave trying to convince some folks that CSI is more often than not irrelevant.

CSI is a very useful tool IF you have hard fill water. It's not totally that simple but it's reasonably close to that and if you do NOT have hard fill water, your CSI concerns are fairly useless What kind of fill water CH do you have out there in ole' Little Rock? I pulled this quote as one among many that was easily found with google.
" Arkansas has one of the lowest averages for hard water in the country at 38 PPM, according to the USGS water hardness measures, Some examples of soft water cities are Little Rock with 26 PPM and Fayetteville with a hardness level of 27 PPM. The hardest water level in the state comes from Pine Bluff, which gets its water from 4 wells that pump from the Sparta Sand Aquifer. "

Burn your time and energy with careful study of the FC/CYA relationship and how algae sneaks up on your pool in mid-summer often undetected.......those are important issues you will face......CSI is not with water like that.
Hold up, I'm really confused by this post. As a plaster/pebble owner, I've always understood the general rule of thumb for CSI as:
+0.6 and above, and you risk scaling
- 0.6 and below and you risk damaging your plaster as the calcium will leach from the plaster into the water.

The OPs CSI is less than -1, so I would worry about damaging the plaster by leaving his water that aggressive all winter.

Furthermore, I've also understood that you can manipulate the individual components of CSI to be out of the ideal range for that component, in order to get your CSI in line. In this example, letting pH drift up to 8.0, above the ideal of 7.8, in order to keep his CSI less negative.

I do agree with the comment that CSI is far less important to fiberglass and liner pools, and that the FC/CYA relationship is the #1 most important ratio for keeping your water clear and sanitary.

You have many more years of experience with pools than I do, so please keep me honest if I am wrong. I have thick skin and am much more worried about managing my water incorrectly and offering up incorrect advice if CSI is not important.
 
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Hold up, I'm really confused by this post. As a plaster/pebble owner, I've always understood the general rule of thumb for CSI as:
+0.6 and above, and you risk scaling
- 0.6 and below and you risk damaging your plaster as the calcium will leach from the plaster into the water.
Might be, but that's not the point. The point is that CSI is pertinent to those pools that cannot maintain normal parameters in a pool......particularly CH. It is not pertinent to those pools that have low calcium water. This pool with a CH somewhere around 30 is one of millions.

Oops! 30 is off the charts too low so now your pool leaches calcium from the pool walls, right? Not at all. Simply add calcium to your pool up to about 300 and test CH every 2 months or maybe longer to keep CH in the 250 - 400 range.

There are millions of pools in this country that have never calculated csi and never will......and a lot of them are in AR which I heretofore did not know.

I remember an old joke about a man sitting on a New York park bench tearing phone pages from a phone book "to keep the elephants away". An onlooker said, "Man, there are no elephants within 2,000 miles!" "Works pretty good, doesn't it?", he said. Same thing applies if you have low calcium water.
 
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Thanks Dave. I'm still processing your post, but will reach out if I have any questions as to not to distract from the OP's thread.

Speaking of, Iain, are you doing okay? Did we answer your questions?
 
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We have awesome water in Arkansas. One of the few perks. I am on my 3rd going on 4th season with a pool but no expert. When the app says to beware damage to plaster my gut instinct is to try to protect my investment. Is the app being overly cautious...?
 
With the cold water temps you are toying with damaging your surface. This may take years to do, but you’re reducing the lifespan of your plaster and increasing the odds you’ll etch your plaster. The App is simply giving you a heads up that you may wanna take action. During the winter it’s suggested to allow your pH to slightly drift up as this will greatly help counterbalance the low water temp. You can read some more in the CSI Article. I wouldn’t rush outside and add chemicals to bump the pH up, but I would suggest avoiding lowering it unless it reaches 8.0 or so.

My larger worry looking at your numbers is your FC level. Get some chlorine in there! 😂
 
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With the cold water temps you are toying with damaging your surface. This may take years to do, but you’re reducing the lifespan of your plaster and increasing the odds you’ll etch your plaster. The App is simply giving you a heads up that you may wanna take action. During the winter it’s suggested to allow your pH to slightly drift up as this will greatly help counterbalance the low water temp. You can read some more in the CSI Article. I wouldn’t rush outside and add chemicals to bump the pH up, but I would suggest avoiding lowering it unless it reaches 8.0 or so.

My larger worry looking at your numbers is your FC level. Get some chlorine in there! 😂

Yeah I've added some liquid chlorine.

I have friends with a pool and the surface is really rough. I'd like to kee mine is as good of shape as possible.
 
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Ok, so don't mean to tailgate on this post, but it's relevant and now I'm nervous. We sustained damage from Hurricane Laura where a LARGE branch busted an unknown bubble in our plaster on our lounge step. Pool needs to be replastered, but following a wedding, college expenses, yada yada, I couldn't pull off the $14K-$16K. Instead, a creative tile contractor friend from church recommended just tiling the step. We went one step further being in Louisiana (Who Dat!!) and ordered a Fleur de Lis medallion from Mozaico.com (40"x40"), and pulled the install off for ~$3K. LOVE IT!

tempImagelgoYt2.jpg tempImageaznhgU.jpg

OK, now to the point. I'm ready this post that caught my eye and now I'm concerned about my chemical activity of late. I SLAMMED my pool with 5% Chloralen bleach from Home Depot after adding filtered bayou water (water rates have sky rocketed here recently). Current tests as of today...

FC: 26 (holding on overnight test)
CC: 0
pH: 8.2+
CYA: 75
Calcium: 225

I added 1gal muriatic acid and added 19+ lbs calcium to bring my level up to 400 today, following my testing. So temps have been in the 30's to 40's at night and now after reading this post, I'm wondering if I've just set myself up for a problem. I want to protect the plaster I have left and kick the can down the road awhile. thoughts?
 

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You did go a little heavy handed on the CH addition. We always recommend adding half the amount suggested by PoolMath then test again and creep up on the target you want. Your Ph is helping you keep your CSI in check just dont lower it below 7.8.
 
Very interesting thread. I too notice CSI drops on the rare occasions my pool gets down to the lower water temps. For me that's mid 70's. It's normally very close to perfect with CSI at a little negative to -.3 almost all the time so I don't really worry about it. But I am an engineer so I can get a little anal. I try not to but sometimes I just can't help it. When temp does get very low I'll let pH rise and that helps the CSI but I also know that at higher pH chlorine is less effective. I'm way more concerned about keeping my pool disinfected than "crossing the line" on CSI for a day or two so I don't let pH rise above 8 on purpose. I guess this is why we use the term "water balance". Change one thing for the good and it can change something else for the bad. My consolation is that so long as I stay in TFP ranges everything works out 99% of the time.

JJ and experts, thanks for the discussion. Very helpful to me.

Chris
 
tlutrick,

So if you don't check your fill water, you don't know what you are putting in your pool and don't really know if CSI is at all relevant. Put another way, there is nothing in your numbers or circumstances that justifies an adjustment unless you are really dead set on chasing csi........but without the CH of your fill water, you have no idea if you should be monitoring CSI at all. I see no reason whatsoever to adjust anything in your pool except chlorine.
 

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