potential problem?

[Donna's Poolboy]

Okay...here's an update. I found a post on another thread that helped me a bunch: circulate the water; then test. We took the cover off the pool yesterday, fired up the pump and let the water circulate for 24 hours. Huge difference. Here's the new set of numbers:
FC 1
CC .5
TC 1.5
ph 7.5
alk 100
cal 150
cya 60

My cya was about 80 at then end of the season last year. When I take into account the amount of water I drained off and the addition of rain/snow over the winter, a cya of 60 seems about right. I guess my 0 reading was a result of the cya "sinking" to the bottom of the pool over the winter (?)

By the way, the pool temp is 48 degrees. I know that's too cold for an accurate cya test, so I warmed the sample water by running the bottle under warm tap water until it was about 75. Is that acceptable or will warming it that way screw with the test results?

 

[JasonLion]

Much better!

Warming up the sample for the CYA test is fine, just don't do that for the FC, CC, or PH tests.

 

[amjohn]

On the water temp issue for testing. What about letting the bottle of pool sample water sit for a day to come to room temp? Room temp for me is 65 degrees.
Does temp not make a difference in the tests?
Also, polyquat- I got mine from amerimerc.com at http://www.amerimerc.com/Pool-Algaecides~poly-60.htm
You can buy in bulk and save. And they have miracle shipping- most times takes them only one day. I cannot even mail a letter to the other side of our two horse town in one day.

 

[JasonLion]

It is important that the FC, CC, and PH tests be done fairly quickly after the sample is taken without any significant temperature change happening. Chlorine can evaporate right out of the sample and the PH will shift with changing temperatures.

The TA and CH tests don't really care about water temperature and can tolerate sample storage fairly well. Though on the CH test you should mix a bit longer after each drop when the sample is cold.

The CYA test tends to give inconsistent results at low temperatures, and is much more reliable at room temperature, or a bit above. The CYA test also doesn't mind if the sample is stored for a while.