CYA barely dropped after draining 50% of pool - WDID?

[linzi618]

As title says. Drained appx 50% of my pool yesterday. Did so via submersible pump in deep end (7ft).

Pool pump turned on this morning at 7. Before draining yesterday i discarded the 2.5 trichlor pucks out of my chlorinator so it is empty. Pre drain chemistry:

‘Before Drain (water from 12 inches (elbow deep) below surface in deep end and tests performed with speedstir)
TC - 2.5ppm
pH - 7.5-7.8
CH - 700
TA - 130
CYA - somewhere north of 100. (I did not do the dilute 50% with distilled test and x2 to get a better read as I didn’t read about that idea until after the pool was drained.

Fill Water
pH - 7.5
TA - 160
CH - 200ppm
CYA - 0

Pool Post Refill ((water from 12 inches (elbow deep) below surface in deep end and tests performed with speedstir)
TC - 0-1 (after adding powder and speed stirring it *barely* turned pink. Barely
pH - 7.6
CH - 500pp,
TA - 150
CYA - 120??????? Did normal test per TF-100 instructions. When the dot still disappeared over 100, i diluted 50% with distilled water (fresh open gallon) and the dot disappeared around just below 60. FML.

Do I need to drain my pool again? I’m gobsmacked. Like I said I removed any pucks from my chlorinator before we drained and the pool pump didn’t turn back on until 7 this morning. Took 12 hours to fill my pool back up after draining yesterday morning so after it was full it sat uncirculating for apps 7 hours as I turned the hoses off at midnight.

I don’t want to commence with my SLAM with my CYA still north of 100, right?

Your help is very very appreciated.

 

[ajw22]

Your CYA was well north of 100. 200+ is not surprising.

Time for another drain about 80% to get CYA to around 30. You know the drill now.

 

[linzi618]

Your CYA was well north of 100. 200+ is not surprising.

Time for another drain about 80% to get CYA to around 30. You know the drill now.

I just cannot believe how far off Leslies was with their CYA reading the last time we had it tested (110 on 4/20).
My poor water bill...
I’m assuming it is safe to drain my pool to almost empty? It’s been in the ground for almost 3 years. We are supposed to get rain today...

 

[Rancho Cost-a-Lotta]

I just cannot believe how far off Leslies was with their CYA reading the last time we had it tested (110 on 4/20).

I can. Before I got my kit and found my CYA in the 120-140 range, I went to two different franchises and got readings of 60 and 90 ppm. They always asked me how I sanitized my pool (tablets) before the tests.

I went to a different local pool store that uses test strips. They came up with 140 ppm. This was more accurate than the previous two tests.

 

[linzi618]

I can. Before I got my kit and found my CYA in the 120-140 range, I went to two different franchises and got readings of 60 and 90 ppm. They always asked me how I sanitized my pool (tablets) before the tests.

I went to a different local pool store that uses test strips. They came up with 140 ppm. This was more accurate than the previous two tests.

Are there consumer CYA test strips? I hate trying to decide whether or not I can still see the black dot...

 

[Donldson]

Mike beat me to it: I can as well.

Unfortunately, the cost of "free" testing can often be quite high. Which would be why we can be quite vocal in our attempt at dissuading anybody from falling in to that trap.

And no test strips! If you are surprised at how far off Leslie's can be, you'll be amazed at test strip results.

 

[Rancho Cost-a-Lotta]

I went to a different local pool store that uses test strips. They came up with 140 ppm. This was more accurate than the previous two tests.

Sorry, I didn't mean for this to be an endorsement for test strips. It was meant to demonstrate the incompetence of the previous two "professional" tests.

You have the best consumer test kit available. Rely on it and nothing else.