CYA numbers bouncing around or bad testing?

G

Guest

Hi guys,

So recently I went through a large drain/refill to get my CYA numbers down. Supposedly before the drain I had 150ppm (or more) CYA. Before drain I had 16078 gallons, and after draining I had 5032 gallons of original water left. Then I refilled back to the ~16k gallon mark. After the week of slowly refilling the pool with well water here was my test results (from the store):

Temp 75
saturation index 0
CYA 61
TC 3.9
FC 3.1
pH 7.3
TA 191
Adj TA 173
Tot hardness 256
Copper 0.5ppm
Iron 0

Around this same time, another test from another store gave me a CYA of 40

I then shocked my pool to ~24ppm, and shocked again a day later to my guess of 12ppm. I haven't added any chemicals in the past week, just filtering as much as possible. Here are my current test results:

Temp 77
saturation index 0.9
CYA 119
TC 9
FC 7.9
pH 8.1
TA 214
Adj TA 178
Tot hardness 282

I was not expecting the CYA to jump up like that. I even had them test again (manually, instead of in the machine). Is there something like my relatively higher FC that could be affecting CYA to make it inaccurate? Or do I need to drain again?

I've attached some pictures of the pool...vinyl liner is very old and wrinkled, and concrete has seen better days. Also the skimmer line is leaking, so it is plugged off in the skimmer and disconnected from the pump, as you can see. Not sure what the 3rd tall PVC line is, maybe it's a winterizing line or something.

Big question is this: If my CYA is where I'm hoping it was, in the 40-60ppm range, then my FC is fine. But if my CYA is really that high at 119ppm, I'm going to have to go through the entire draining cycle again, which was a pain in the butt and a strain on my well.

Also, any other suggestions on what to adjust in my chemistry, and what order? I know pH is a little higher and hardness too.
 

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Since you only added liquid chlorine, probably testing error. Now you can see why we don't trust pool store testing. Like Richard said, if you want to take control of your pool, you will need to get one of the recommended test kits, which are conveniently linked to in my signature.
 
I had three different stores (two were the same just on different sides of town) test my pool water. It was all a sample taken from one area at the same time.

I got three completely different test results! The money to "fix" my problems ranged from $75 and $125 and to bring back more water after I put in the stuff they wanted to sell me. I just walked out laughing!

See I had tested my water with MY pool kit and it was RIGHT on the money. My water looked great and felt great! There was NOTHING wrong with my water. I even told the pool store the water looked fine. "Oh but there WILL be problems if you do not buy and put in.....". LOL

Kim
 
Yeah, so I went ahead and got a test kit, but it probably won't arrive for a week. I was putting it off because constantly buying new reagents is annoying, but I guess that's the price to pay.
 
I ordered my test kit when I ordered my pool. I went ahead and ordered the reagents I knew I would need the most as well. I used it last summer and am still using it this summer. I think I will have plenty for next summer so...........

Kim
 
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