Confused about chemicals

Jun 16, 2016
27
Kansas City, MO
We had to fill our 15'x48" Intex pool over the course of a couple of days and it's pretty well full (needs maybe another 6 inches). I bought a bunch of stuff after work yesterday, including a couple of test kits (Chorox strips and an hth 3-way liquid tester) to use while I wait for my TF kit to arrive. This is the stuff I bought and numbers from both kits, but I'm not completely sure what my first move should be.

Items purchased:

Borax
hth stabilizer
Baking soda
Chlorinating Liquid 10% Sodium Hypocholorite

The hth test has a pH reading that was higher than my tester (8.2). Chlorine and bromine were 1 and 2, respectively.

And the test strip levels:

Total Hardness - 250
Total Chlorine - 3
Free Chlorine - 0
pH - 8.4
Total Alkalinity - 40
Stabilizer - 100

Now, I realize those numbers are probably off, but I plugged them into Pool Math. It said I should add 27 oz of bleach, 28 oz of stabilizer, and muriatic acid. I don't have any muriatic acid, but I noticed that it states (under stabilizer) that it will lower the pH.

So what I'm thinking is that I should add the amounts of bleach and stabilizer (pump in running), wait an hour and retest. I realize I'm kind of winging it at the moment, but I also don't want it to turn into a swamp.
 
Whoa!! Please don't add any stabilizer (or calcium) to that pool. Your CYA (stabilizer) is far too high already if you can believe those test kits your bought. Intex pools don't need calcium hardness, but I'm not sure if Kansas City water is naturally hard? How does your water look?

I suspect you're going to need to drain about half that water and replace to get the CYA level down.

You also need muriatic acid to drop the pH.

You might not even need the Borax and Baking Soda so don't worry about them now.

Add 1/2 gallon of bleach daily until your good tester arrives (which one did you order?).

Holler back with any more questions. It will get easier I promise. You just have to tweak it at first.

Homework: ABCs of Pool Water Chemistry
 
Thanks for the quick reply, YippeeSkippy! And you're right about the stabilizer; I forgot to plug that number in pool school! According to the latest report from the Water Dept, the average total hardness is 107 ppm, with a range of 69-127, so moderately hard. The water looks clear and isn't cloudy.

I'll do the bleach only until my TF-100 arrives. I'll also pick up some muriatic acid and will keep reading.

ETA: Thought I'd add more detailed numbers about the water hardness number, since they might be helpful. The first number is the average and the other is the range, city wide.

Alkalinity ppm - 32, 17 - 72
Ammonia ppm - (as N) - 0.23, 0.05 - 0.61
Calcium ppm - 37.4, 34.2 - 42.4
Magnesium ppm - 5.29, 3.63 - 6.83
pH - s.u. 9.8, 8.6 - 10.3
Sodium ppm - 68.3, 44.3 - 80.5
Sulfate ppm - 184, 66 - 227
Total Hardness (as CaCO3) ppm - 107, 69 - 129
 
Today's update. I didn't end up putting anything in last night, since it was dark. We got some rain today and eyeballing it, it looks like we got maybe 1/4 inch. I did two tests with the strips, one an hour after the rain stopped (before adding anything) and an hour after adding about 44 oz of the bleach. This time I took some pictures. A friend suggested I test the strips with distilled water, so I've got 4 pictures. I'm posting pics so get a second opinion, since I'm not sure if I'm reading these correctly.

Distilled water

distilled%20water%206.26%202_zpswnyferyf.jpg



Before chlorine

before%20chlorine%206.26%202_zps26nwhbs0.jpg



Hour after chlorine

hour%20after%20chlorine%206.26%202_zpssgb9bzcf.jpg



Two hours after chlorine

2%20hrs%20chlorine%20direct%206.26%202_zpsyrbx3njn.jpg
 
I don't think your original stabilizer (AKA CYA) number at 100 is correct. If you're filling with city water (and now some rain), there wouldn't be any in there. The test strips seem to say that the Stabilizer is 0. If it was really 100, that would be way too high. You want it ultimately to be around 40.

I suggest waiting until you get your test kit before you add anything other than the bleach as suggested by Yippee above. Then, do all the tests and give us full results.
 
I don't plan on adding anything but bleach until my tester arrives, but I thought that pictures might be useful. When I tested before, the stabilizer/CYA looked more pink than orange. There's a pink tinge to the right of that section on the bottom picture and that's what the entire pad looked like before. That said, it might have been a bad strip or user error. Actually, I just remembered that I took a picture of that strip. It's not the best lighting, but it'll have to do.

20160625_201845_zpsxkgeb3wf.jpg
 
Using test strips at all is not a good idea in the best circumstances following the directions exactly and reading them in perfect light at exactly the right time. Taking a picture of them and posting them on the internet for people to try to interpret with who knows what kind of screen settings, phones, tabs (me), computers, night mode and whatever else is an even worse idea.

I personally would do nothing to my pool based on that information.
 
My tester came today and I was able to do my first testing. I took my time (and rather enjoyed the process) so I think it is accurate. Also, the only thing I've put in the pool is chlorine.

My results:

FC – 6.5
CC - .5
pH – 7.5-7.8 (I kept wavering back and forth on this one)
TA – 30
CH – 150
CYA - ? (Not sure what was supposed to happen, but I filled the vial with the solution and could still see the dot.)

Thoughts?
 

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MarianParoo, I didn't see your question until now. The solution on the first CYA test wasn't cloudy at all, but I also wasn't sure what I was supposed to be seeing.

I ended up testing 3 times today. I know that's overkill, but my speedstir came today and wanted to play with it, as well as get a feel for the testing process.

The evening of the 29th, I added 14 oz of CYA. Pool Math said I needed 28 oz, but I wanted to go slow with adding things. Also, my sock wasn't quite big enough (need bigger feet). It sat next to the running return and was gone by this afternoon.

I did the CYA test only once today and that was prior to adding the chemicals below. My CYA was 20.

On the 30th, I added:

17 oz bleach
37 oz baking soda
14 oz CYA

After 6 hours, these are my numbers.

FC – 4
CC – .5
TC – 4.5
pH – 7.2-7.5
TA – 60
CH – 150


I have a question on the FC/CC test. I realized by accident, on my second drop test, that the water looked clear when I added the 5 drops of 0003, but when I sat it down on a piece of white paper, I could see a tinge of pink. With all three tests, it only took an additional drop to make it completely clear. I noticed this by accident; the magnet kept rattling and I happened to set it down on a piece of white paper. Should I be getting it to "clear", then check it with a piece of paper to confirm it's clear before I do the test with the 0003? Does that small of a difference matter?
 
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