"Mort" wrote in message y.com...
With this kit, you take a sample of water, then add 3 drops from bottle #1,
(which makes the sample look real cloudy) mix, then add 7 drops from bottle
number two (turns it real pink, almost red). According to the chart it
should be a light pink at this point but it is way off. Then you start
adding drops from bottle #3. You multiply the number of drops by 20 and
that gives you your mg/L. (which I think is the same as ppm right?)

My problem is, is that the sample never matches the color on the chart
exactly. Supposedly, it will change from light pink to violet (they give
you two colored boxes to compare it to) when the test is complete. It goes
through so many shades of purple and red and it never matches the colors on
the chart. It is impossible to get a good reading.

I am using SeaChem calcium test and they also use titrate method.
http://www.drsfostersmith.com/Produc...133&in_merch=1
The point the measurment is ended for SeaChem test is when the color of the
sample turns blue (originaly pink). The transition is rapid (one drop or less).
You may note the amount you added and add more - if the coloro does not change
the noted value is your reading.

I am also reading high calcium with low alkalinity - I use SeaLab #28.