No change in levels.

[kenny]

I added 5 cups of calcium granular yesterday to increase CH from 275 to 300. Today it's still measuring at 275. Should I wait to restest again or add more?

Had same problem with CYA. Added granular stabilizer last week and still no change as of today?

FC 7
CC 0
PH 7.6
TA 90
CH 275
CYA 50
SALT 3900
BORATES 50

 

[JasonLion]

5 cups of calcium would have increased the CH level by about 15, which could easily fail to show up on the test when you are testing by multiples of 25.

If you made a similarly small change to the CYA level it is just as likely not to show up.

 

[Guest]

Precision of the CH test is either +/- 10 ppm or +/- 25 ppm depending on the sample. That means for a 25 ml sample your test results could vary by as much as 20 ppm and still be 'within spec' and for a 10 ml sample the variance is 50 ppm! Raising your CH from 275 to 300 ppm will not have any real effect on your pool in real world conditions. I would not worry about making changes in CH unless they were 50 ppm or greater (unless you are right on the boarder of the recommended levels, then I would say to get yourself in the middoe of the range.) If you look at this chart of recommended leves you will see that the smallest range we give for CH is 100 ppm. Small changes are not going to have any effect.
pool-school/recommended_levels

How much were you trying to move the CYA? If it was 20 pm or less it is very possible that you would not see it on testing. My recommendation would be to bring your CYA up to 80 ppm.

I've said it before and I will say it again. It is not necessary (nor is it even desirable) to micromanage a pool. KISS!

 

[kenny]

I'm attempting to raise CYA from 50 to 80. Added stabilizer today and will retest next week.

 

[Guest]

I'm attempting to raise CYA from 50 to 80. Added stabilizer today and will retest next week.

 

[kenny]

I don't get it. On top of the initial 5 cups, I added the rest of the bottle which was a total of 5 lbs. of Calcium and my CH is STILL testing at 275. Why is it not moving? I'm just dumping the granular into the skimmer.

 

[JasonLion]

What test kit are you using?

 

[kenny]

Taylor FAS-DPD test kit. When I do the test, the R-0011L drops seem to come out smaller than the other reagents. Is that normal as well?

 

[JasonLion]

Try wiping the dropper tip with a damp tissue at first and every couple of drops and see if that makes any difference.

 

[kenny]

I think I found the problem. The drops from the R-0011L appeared to come out smaller and a bit thick. I shook the bottle up first and then put the 3 drops in and the test showed CH at 325.