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fairfieldmania
07-11-2012, 10:15 AM
I've read on here and been told to use the 10 ml sample rather than the larger sample sizes in order to save the reagents.....can someone please tell me exactly which tests to use the smaller sample?

CC and FC...you have the option to use either one...but if you use the 10 ml, do you only use one scoop of the powder?

ph you are supposed to use the 44 ml and 5 drops of R-004...if I use the smaller sample size...how many drops??

TA - 25 ml sample with 2 drops of R7 and 5 drops of R8....again, is this the test to use the smaller size?...how many drops??

CH - 25 ml with 20 drops of R10 and 5 drops of R11L...same questions

CYA - I assume this is one test that the recommendation to use the smaller sample tube doesn't apply...

Watermom
07-11-2012, 12:31 PM
You need to use the full 44ml on the pH test. Also, the CYA test is 7ml of water and 7ml of R-0013.

On the chlorine tests, if you use the 10mL or the 25mL test either one, you only have to add one scoop of powder. If one scoop doesn't turn the water pink, you can add the second one.

On the other tests since I don't run them too often, I typically just use the 25mL sample. But, if you think your TA or CH are very high, on the bottom of that test's directions inside the K-2006 lid, it tells you how to use a 10mL sample instead.

waterbear
08-01-2012, 11:01 AM
If you are new to testing I would suggest using the 10 ml sample on the CH hardness test since this test can take a long time to do if your calcium is above about 150 ppm. This will allow you to see the color changes quickly (since they can take many drops of reagent to change fully using eh 25 ml sample.) Also, IMHO, if your calcium hardness is above about 300-350 ppm then a precision of 25 ppm is certainly close enough and a precision of 10 ppm is overkill, particularly if you are not worried about computing the calcium saturation index.