Rebalance Water For New Vinyl Liner

May 20, 2015
24
cochran\georgia
Test Results At 10AM, 9/11/15. FC-.5, CC-0, pH-7.8, TA-160, CH-175, CYA-?. Tested 12 hours later after after adding 1.25 gallon of liquid chlorine (sodium hypochlorite 10.5%) and only change was FC-6, CC-.5, CH-200. The pool leaked an inch of water roughly every 12 hours for 6 days after the initial refill before a leak around the light and steps was repaired. The water was replaced daily with a hose from our well. The water has stayed clear thru all this. I had to fill the CYA tube full to make the black dot disappear. The only CYA added was thru 4 small barrell shaped chlorinator tablets (2 to a skimmer basket) thru all this and they still haven't completely dissolved as I remove them when the pump isn't running. Test Strips show the CYA to be in the 30 to 50 range but I know these are supposedly not accurate. I think I need to get my CYA up and possibly my TA down. I don't mind buying the liquid form of CYA if it will speed up this rebalance as I am anxious to close my pool. Current temperature is 79 degrees. Suggestions welcome!!!
 
You really don't want to close the pool with water temperature in the 70's. It is best to wait for the temperature to fall into the 60's, the lower the better.

Algae reproduction is stunted (but not eliminated) as the temperature drops. In the 60's it is almost nonexistent. That is why we teach close late and open early to avoid a green pool.

Any chlorine in the water will be gone within a few days of closing the pool. If the water is still in the 70's you are giving the algae a great place to live.
 
Any suggestions on the chemicals?
Get some chlorine in your pool pronto and keep it in there until your temp get's down into the 60's. Bring your CYA up into the 30-40 range or your Chlorine will be consumed everyday by the sun. The liquid CYA will be much faster.

read "The ABC's of Pool Water Chemistry" up in Pool School. That'll help you understand why you need to do these things.
 
I just bought some liquid CYA that is 35% Monosodium cyanurate monohydrate and Percentage of Constituents Ineffective as Spray Adjuvants 65%. It's equivalent to 30% cyanuric acid. The product says it is a salt and not an acid with a pool friendly pH, so it will not damage pool surfaces or equipment. It was expensive and I only bought a gallon and haven't used it yet. I think I'm going to need at least one more gallon. Comments or Suggestions Welcome before I use it! There are no instructions on how long to wait before testing for CYA after adding the product. To be safe, I figure 24 hours.
 
The only msds that I can find for 35% has the remaining percentage as water. What is the brand name of the product you purchased?

You should be able to test CYA as soon as water circulates well, about 2 hours to be safe. Some may say 24 hours.
 

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After adding 2 gallons of the liquid stabilizer, my CYA is now 40. Thru this 3 or 4 day process my pH has gone from 7.8 to 8.2. My CC is currently 3 and my TA has been in the 150 to 160 range since the pool was refilled. Water temp is down to 74 degrees and the pool looks good. Pool business says leave pH and TA alone. Comments or suggestions?
 
Use muriatic acid and lower your pH to 7.2.

Adding MA will also bring down the TA a little, its a bit of a process and takes time, but the TA will eventually come down as you continue to control the pH. The TA as it is, isn't a problem though.

If your CC is really 3, then thats indicative of the FC being oxidized by organics. If I were you and since the water is clear, I would raise the FC to SLAM level (16), and keep it there for a day or two and then do a Overnight Chlorine Loss Test and see if that will get rid of the CC's.

If you have more than 1ppm loss overnight, then there are organics, (most likely algae), consuming the chlorine.
Keep the FC level at 16 or slightly higher, until you dont loose more than 1 ppm FC overnight, and you have .5 CC or less.

Adjust your pH to 7.2 before raising the FC level though.
 
Thanks for the pH and slam advice Dave. After looking at Marian's question, I realize I mistakenly posted my FC as CC. Sorry for the confusion. I assume I should still lower my pH and ignore the slam. Sorry for not posting all my #'s. The pool hasn't run for 3 hours but i went shoulder deep for a water sample in the deep end. My FC is 2 and my CC is .5. I plan to start the pool up at 5AM before I leave for work and add a half gallon of chlorine. When I get home around 3PM tomorrow, I'll start working on the pH. I'll check this thread before I start on the pH. Once again, thank both of you for your help!
 
ahhhhh OK.
well .5 CC sound MUCH better than 3! :)
You shouldn't need to slam it.

Yes, you should still lower the pH, 7.2 to 7.5 would be a good number.



Thanks for the pH and slam advice Dave. After looking at Marian's question, I realize I mistakenly posted my FC as CC. Sorry for the confusion. I assume I should still lower my pH and ignore the slam. Sorry for not posting all my #'s. The pool hasn't run for 3 hours but i went shoulder deep for a water sample in the deep end. My FC is 2 and my CC is .5. I plan to start the pool up at 5AM before I leave for work and add a half gallon of chlorine. When I get home around 3PM tomorrow, I'll start working on the pH. I'll check this thread before I start on the pH. Once again, thank both of you for your help!
 
FC 7.5
CC .5
pH 7.8
TA 130(pink) 140(red) again
CH 175
CYA 40?

I added a half galloln of muriatic acid after my last post and the pH came down to 7.5. A few days later, it was back to 7.8. I put half of the remaining half gallon of acid in and it returned to 7.5 again. A few days later I put the remainder of the gallon in as it was back to 7.8 again and today I'm back to 7.8 again after a few days. Sorry I can't be more specific than "a few days" as I know you probably need that info. Does my TA need to come down? Also I have fiberglass steps and am curious about my CH being harmful for them. Temperature is 72 and water is clear. I almost forgot. How many days of what temperature does it take for an inground pool to reach 60 degrees?
 
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