Start-up water Chem questions...

jennbostwick

Active member
Jun 12, 2020
40
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I am on day 4 of start-up (new plaster)with our SWP. I have been testing water daily and adding muriatic acid as it says on PoolMath. We will not add salt for another 25 days or so. If I balance all my water chemistries, will they change when I add salt or does salt not have any effect on the results. That may be a dumb question. I don’t know what I am doing and that’s why I’m here. I have my reading too and would like advice.
pH >8.2 every day
Cl: 0.5 every day
TA: 130, 100, 90 today
Ca: 100, 100, 125 today
CYA: only tested today = 15!

Based on PoolMath, I need to add a lot of things. Can someone confirm? Basing this on 30k gallons.
CYA - 15 lbs
Bleach - 156 oz
CaCl - 90 lbs
41 oz - muriatic acid.
 

Stoopalini

Gold Supporter
Jun 8, 2020
383
Central Texas
Using 30k gallons as the volume, and the legacy PoolMath web page .....

90 lbs (1440 oz) of calcium chloride will raise your CH by 324, leaving you with 449. Is that what you want? What does your PB say it needs to be during plaster curing?

1599766090204.png


15 lbs (240 oz) of granule stabilizer - CYA - will raise the CYA by 60, landing you at 75, since you said you're starting at 15. Although, how did you test to arrive at 15? Either way, adding all of this at once will tank your pH, so definitely spread it out if you plan to add this much. Do it over a few days, slowing approaching your target while allowing the pH to recover between doses.

1599766221846.png


41 oz of MA will lower the pH by 0.33 ... but also note above that stabilizer (CYA) will lower the pH as well So I wouldn't do both of these at the same time.

1599766289665.png


156 oz of 10% bleach will raise FC by 4.1, leaving you around 4.6 if starting at 0.5

1599766367773.png

Are you using solely liquid chlorine/bleach while the plaster is curing, or are you using other types of chlorine as well?

Note the Chlorine/CYA chart, and adjust your FC target as your CYA rises: Chlorine / CYA Chart - Trouble Free Pool
 

duraleigh

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I would suggest a little simpler approach. Please read "The "ABC's of Pool Water Chemistry" up in Pool School. It's the basis for everything we teach.

Then, (in this order) using the dosage of muriatic you calculated get your pH down into the 7's and keep it there, checking it daily until you have knowledge of how it reacts.

Next add only 8 lbs of CYA.......test it in 48 hours and report your results.

Daily, add enough FC to keep your chlorine around 5-7 ppm.

Leave your CH alone for now.
 
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jennbostwick

Active member
Jun 12, 2020
40
ok
I would suggest a little simpler approach. Please read "The "ABC's of Pool Water Chemistry" up in Pool School. It's the basis for everything we teach.

Then, (in this order) using the dosage of muriatic you calculated get your pH down into the 7's and keep it there, checking it daily until you have knowledge of how it reacts.

Next add only 8 lbs of CYA.......test it in 48 hours and report your results.

Daily, add enough FC to keep your chlorine around 5-7 ppm.

Leave your CH alone for now.
Thank you! Added 4 lbs of CYA tonight. Will add the other 4 tomorrow. Added smaller amp. of muriatic acid.
Have you read this from TFP's Pool School-

Maddie
Yes, ma'am!
 

jennbostwick

Active member
Jun 12, 2020
40
ok
So, I feel like I'm not getting anywhere. I'm testing daily, adding chemicals daily, brushing daily but my levels don't seem to be changing much. We won't be adding salt for another 20 days or so. The heater is not on. Water temp. is around 70 degrees daily. Children "swim" for about 5 minutes every day.

pH has been 8.2 or higher every day. Dipped to 7.2 shortly on day 4 after adding muriatic acid, but back up to 8.2 the next day.

Chlorine levels have been close to 1 every day except on day 7 after adding 3 pounds of 73% Cal/Hypo and 10 lbs of baking soda. Next day back to 1. Had previously added one pound of 73% Cal/Hypo on day day 4 with no results. Added another pound today.

TA started on Day 1 at 130 but got down to 80 for 3 days, now back up to 120 for last 2 days. Have been following PoolMath's suggestions and adding muriatic acid almost daily. I am diluting it with water and then pouring in deep end. Am I adding this wrong?

Calcium started at 100, peaked at 150 on Day 6 (due to stabilizer?) but is now resting at 125 for last 2 days.

CYA has been almost non-existent until Day 7. Was 30 then dropped to 20 yesterday.

I added 8 lbs of stabilizer in two doses a day apart on days 3 and 4.

Am I testing too often? Do I need to go have a glass of wine and chill out?
 

duraleigh

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It doesn't seem you know WHY you are testing and it seems as if you have some testing errors.

So, Please read "The "ABC's of Pool Water Chemistry" up in Pool School, It helps you understand why you are testing and then will teach you how to move your parameters to meet TFP guidelines.

What does your water look like? Do you intend to close your pool for the winter?
 

jennbostwick

Active member
Jun 12, 2020
40
ok
It doesn't seem you know WHY you are testing and it seems as if you have some testing errors.

So, Please read "The "ABC's of Pool Water Chemistry" up in Pool School, It helps you understand why you are testing and then will teach you how to move your parameters to meet TFP guidelines.

What does your water look like? Do you intend to close your pool for the winter?
I have read all of the things. I am testing because I have a new pool with new plaster and I was told to test my water and get my levels in order. I bought the test kit from TFP and am using the Pool Math app. There are lots of red exclamation points on my overview after logging in my readings. So I am adding the chemicals the app says to add and I test again the next day to see if it has made a difference.
 

Stoopalini

Gold Supporter
Jun 8, 2020
383
Central Texas
Oh, I see .. to raise the TA. Do you have an autofill? The numbers your poolmath log show don't seem to correlate to the chemical additions you are making. Could you be losing water, and an autofill is making it up without you knowing?

Or maybe the pool isn't 30k gallons?

If none of those are it, then I'd take a hard look at your testing process, and make sure it is producing accurate results.
 

duraleigh

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Okay. You have some testing errors.
pH has been 8.2 or higher every day. Dipped to 7.2 shortly on day 4 after adding muriatic acid, but back up to 8.2 the next day.
Ph doesn't swing that wildly. I am not sure where the error occurred but let's clear them up one at a time. What is your current pH? Is it still at 8.2?