CYA Problem

[Thykon]

Need some guidance folks,

I purchased the TF test kit and can not get a CYA reading.

Its not that it is too high, but I can see the black dot right up until the vile begins to overflow.
I have some aquachek test strips I bought for just quick spot checks (I have nothing good to say about their indication) and although difficult to get a real reading, it looks generally low 30-50.

I purchased some stabilizer to add from my local pool store and after some insistence from the owner that a pool as old as mine couldn't possibly have a reading that low, I brought in a water sample.

They claim that the CYA reading they got is at "100" and I don't require any stabilizer to be added.

I'm assuming that in the presence of a CYA value of 100 my water would be very milky looking after adding the reagent. This is not the case.

My PH is a little high (~7.8), but I haven't read of any factors that could cause my reading to be so low.

Am I missing anything here?
I have done three tests now and several strips and all show low ratings.

What should I do?

 

[elwood58]

You should trust your own readings more than the pool store. Add some CYA, but do it slowly. Give it 4-5 days to show on your test.

 

[linen]

In addition to waiting a few day to test after adding, I would review the extended test kit directions for cya. In particular, make sure you are doing the test outside with the sun to your back and the vial held about at your waste looking down through it.

I too would ignore the pool store and test strip results.

 

[spidey07]

And make sure you are shaking the heck out of the CYA test. This is positively required to get the precipitate.

 

[JasonLion]

Your test result is the expected behavior when CYA is zero, or near zero. That isn't particularly surprising if you just opened for the season as many people lose CYA over the winter.

 

[Thykon]

Thanks for the reassurance guys.

I'll follow my original plan and slowly raise the stabilizer levels.

Since, I'm in the process of opening the pool for the summer and currently running through the filter/backwash dance.
Is there a recommended method to add powdered stabilizer at this time?

I have read that typically you add it to a sock and let it dissolve in the skimmer.
But in my case, wouldn't some/all of that be lost in the backwash stage?

--Anthony

 

[JohnN]

We recommend adding it to a sock and tying it in front of a return. There was just recently a post with a picture of this method, that I will look for later (unless someone else finds it first).