Conflicting information for testing CYA

[SumoSimo]

This page says to glance and not look for the black dot, but this page says to continue pouring until "all traces of the black dot at the bottom of the view tube completely disappears, even after you stare at it for several seconds."

Which one is right?

 

[mknauss]

The wiki is from our personal experience. The Pool School article reiterates the Taylor instruction.

I use the glance method. We do need to resolve those two articles.

 

[Mdragger88]

I do a combo of both by pouring my solution back in the bottle & retesting 3 or 4 times then kinda average all the results to be sure my eyes aren’t playing tricks on me.

 

[ajw22]

Read this to confuse you further, or maybe not…

CYA Testing - Further Reading

www.troublefreepool.com

 

[PoolStored]

The best thing I ever did was buy the Standards and run the test so you know what it is supposed to look like. Gold.

R-7065 CYA Standard 50ppm (2oz)

tftestkits.net

I can repeat the test very quickly now. @mknauss is right. With the standard, and a glance, you will not see the circle. If you stare you will. The standard is THE best teacher. Really hard to get from words.

 

[HermanTX]

I fill to each decade line then glance in the tube. Then fill to the next higher decade level and glance again. When I cannot see the black dot, I use the measurement that I last saw the black dot. Very consistent in results - IMO

 

[SumoSimo]

Interesting approaches. I also found this product on YouTube. Has anyone here used this before? If so, thoughts?

 

[PoolStored]

It's the same thing, just that you are moving the dot vs. filling solution. I think Taylor has or had one like it with the movable dot. The problem is still the same: what does it look like when you have the dot obscured.

The standard taught me what it was supposed to look like.

 

[mknauss]

Has anyone here used this before? If so, thoughts?

Also called the Blue Devil test I believe. Works OK for 60 ppm and under. Does not allow any refinement of levels from 60 to 100ppm. Not a big deal, as most of use with SWCG just want to be above 60 ppm.

 

[HermanTX]

Interesting approaches. I also found this product on YouTube. Has anyone here used this before? If so, thoughts?

I have found it much harder using that slide. First you have to use the slide to stir the solution, Next, you have to hold the slide while you pick up the whole tube to see the position of the slide at the water level. Not very accurate. I know of 1 pool store that uses it as well and when I have them test water (for fun), the CYA is always off by 20 or so ppms. I think it leads to a lot of inconsistency.
With the drop test into the tube, you do not have to hold the slide and you mix your solution prior to putting it in the tube.

 

[SumoSimo]

I'm liking the glance approach. Got a CYA of 40. The stare-at-the-dot approach drove me crazy.

 

[Saturn94]

Glance approach here. Much better for my sanity.

 

[revitup]

I have found it much harder using that slide. First you have to use the slide to stir the solution, Next, you have to hold the slide while you pick up the whole tube to see the position of the slide at the water level. Not very accurate. I know of 1 pool store that uses it as well and when I have them test water (for fun), the CYA is always off by 20 or so ppms. I think it leads to a lot of inconsistency.
With the drop test into the tube, you do not have to hold the slide and you mix your solution prior to putting it in the tube.

I have both the pentair and Taylor tests. They don’t really match up too well. Difference of 20 or so .