Tested vs. Calculated CYA

[louiss3000]

Hi All,

After lurking for some time, and learning a great deal, I discovered why my chlorine levels were so high, and my water still green. Of course, my local pool store said "add algecide" and more tabs in the feeder.

Long story short, I drained the pool, and started from scratch. Everything is now right, except possibly CYA. The Pool Calculator says 5 pounds of stabilizer should yield 50ppm in 12460 gallons. When the pool store tests the water, they say 90ppm.

Who should I believe? I have not yet invested in a "real" test kit. Soon.

Thanks to all the posters here that have taught me so much...

TC 5
FC 5
CC 0
Ph 7.6
TA 80
CH 165 target 300
CYA 50 or 90 ??

 

[JasonLion]

Invest in a real test kit. I would not trust the pool store results.

The CYA level may or may not be 50. 40 and 60 are certainly possible. There is even a very remote chance that your level could be 90, but I very much doubt it.

 

[Butterfly]

Hi louiss3000 and welcome

I agree w/Jason. If you added 5lbs., you should be close to 50. Do not trust the pool store tests.

The best investment we made in our pool is the kit. I suggest the TF100, link in my sig.

For chlorine doses, I'd treat the pool as having CYA of 50.

You've done your homework and got your numbers looking good. Your Ch target looks good, too.

Now how about a pic? :lol:

 

[louiss3000]

Follow up:

To get a second opinion, I took a water sample to the other chain pool store. I got similar results on all except CYA. They say 50ppm. Just as The Pool Calculator predicted. (Recall the first store said 90)

Again, I thank everyone for the knowledge gained in these forums...