Calcium Hardness test interference

[malu95]

Use a 10 ml sample. Each drop of R0012 to blue is 25 ppm CH. A SpeedStir really helps.

I suggest you follow the metals interference process described in Calcium Hardness

Another option is to cut the pool water 1:1 with Distilled Water. Then use that mix for the 10 ml sample. Do the test and double the results.

Hi quick question. By this do you mean you do 5ml pool water and 5 ml distilled water? Or 10ml and 10ml?

 

[mknauss]

Hi quick question. By this do you mean you do 5ml pool water and 5 ml distilled water? Or 10ml and 10ml?

I use 15 ml of pool water and 15 ml of distilled water, mix it well, then pour off until I have 10 ml of sample left and do the test protocol. Double the results.

 

[malu95]

I use 15 ml of pool water and 15 ml of distilled water, mix it well, then pour off until I have 10 ml of sample left and do the test protocol. Double the results.

Thanks! So this is the color that I get (see picture). It is not deep blue but it has a blueish undertone. Is this a good end point? I wasn’t sure if that’s what they meant by “purple” when they talk about interference or if that is good enough.

 

[mknauss]

I call that the endpoint. The purple is more maroon to me.

 

[malu95]

I call that the endpoint. The purple is more maroon to me.

Excellent. Thank you!