Brand new in-ground pool is cloudy, pH is high, chlorine is low

I searched this forum, but could not find any thread to help me...

My in-ground, 15,000 gallon (16’x32’, 3-6’ deep), plaster/gunite pool was completed Sunday, May 21st. They filled it and a guy came out on Tuesday evening, May 23rd, to start the filter, add the chemicals and show me how to maintain the pool.
After he added a bunch of chemicals, the chlorine level was at least 3.0. (I have a Pentair 5-in-1 test kit that tests for chlorine/bromine, Ph, acid demand, and total alkalinity.)
The pH was about 7.6-7.8.

On Wednesday evening, I tested the chlorine and it was non-existent. The test kit showed the sample as totally clear, no yellowing. The pH was at least 8.0, if not more.
I wasn’t able to get any chlorine tablets (I have a Pentair Rainbow 320 Chlorinator) or Muriatic acid until Thursday evening. After adding the chlorine tablets and 3 pints of acid, the chlorine level was still non-existent and the pH was still at or above 8.0.

I re-tested Friday morning and the chlorine is now existent, maybe 0.3 (it’s slightly higher if I get water near one of the jets). The pH is still at or above 8.0.

The water is also slightly cloudy. I can see the white filters at the bottom of the deep end, but not clearly. I’ve been brushing the plaster daily, does brushing cause it to be cloudy?

Is all of this normal for a new pool? Will it take a few days or weeks to get the chlorine/pH levels where they need to be?

PS: I would like to follow the Hamilton Index (it’s easier and cheaper, right?), which calls for a higher pH, but I read on these forums that you can’t use an in-line chlorinator with the high pH method. Why not?

Your PH is high because the plaster is curing. You want to keep the PH below 7.8 otherwise you will get scaling on your pool and equipment. Search the forum for the bleach calculator Mike made, and it will tell you how much acid you need to add to get your PH down. My understanding is that you will need to add acid pretty regularly until the plaster cures (60 days?).

You will need to post your CYA level before your clorine problem can be commented on.

You don't have any CYA, (aka stabilizer), which is allowing your cl to be eaten up by the sunlight. You need to find out if any stabilizer was added to your pool at startup. If so, after a week or so you should be able to see a Cl residual. if not, you need to get some stabilizer and add it to your pool, through the skimmer, and not retest for it or backwash for at least a week until it completely dissolves.

I don't know much about the Hamilton index, but trichlor tabs are very acidic, and I can see where it would be impossible to run a high pH pool if you're using trichlor!

Janet

Thanks for the info.

I thought the trichlor tablets had a stabilizer in them.

I did get a chlorine reading, and now it's at or above 3 (my kit only goes to 3), so I'm trying to play around with the dial setting on my in-line chlorinator. (Does the dial really work to reduce or increase chlorine in the pool?)

My total alk is high, it started at about 320 and now I've got it to 250. I'm adding a gallon of acid per day to lower it. I assume I shouldn't add 3 gallons of acid all at once to lower it drastically, right?

My pH is good, about 7.8.

Should I test the water at the same time everyday?
Does it matter if I test at 6am or 6pm?
Should I test right before or right after adding chemicals?

There is a sticky thread in the "Total Alkalinity" forum which explains how to reduce the TA number very effectively.

As far as the testing - I wouldn't do it right after you add chemicals - as they need time to distribute. CYA takes a few days to a week to dissolve.

My understanding is that the CYA in the tablets is minimal and that it is normally recommended to put CYA in at start-up to at least 30ppm. Then you can keep using the pucks until the CYA approaches 50ppm.

Quote:

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Originally Posted by Simmons99

There is a sticky thread in the "Total Alkalinity" forum which explains how to reduce the TA number very effectively.

As far as the testing - I wouldn't do it right after you add chemicals - as they need time to distribute. CYA takes a few days to a week to dissolve.

My understanding is that the CYA in the tablets is minimal and that it is normally recommended to put CYA in at start-up to at least 30ppm. Then you can keep using the pucks until the CYA approaches 50ppm.

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Actually, I LIKE trichlor tabs/pucks for new gunite/concrete pools, espec in floaters, but chlorinators are good. They will function 3 ways:
1) they will keep a steady stream of chlorine flowing without you adding. This compensates for the time it takes for the CYA to build up.
2) they are extremely acid, which you need to fight the high pH of the curing process.
3) they dump in CYA, which you need. I would not be so leery about testing my water for CYA as has been suggested. The CYA in the pucks is constantly being added. Plus, CYA's job is to keep chlorine from dropping to 0, something not likely to happen as long as you have pucks.

For your T/A, you need to lower your pH to 7.0-7.2 At the time, T/A will measure much lower than now. Then aerate your water to raise pH without raising T/A. Repeat until your T/A is at or below 125. IOW, follow the thread listed above by someone else!