Water testing question


New member
I didn't know where else to post this question...
I have the AP test kits. A couple tests require that you add one drop of stuff, shake the tube, add another drop, shake, etc. til you get to where the color changes to get your reading.
If you know that you're gonna have to add 15-20 drops, can you add 3-4 drops at a time, shake, 3-4 drops, and shake until you get close to your usual reading and then add the drops one at a time to get the real reading?
The last two times it took somewhere around 20 drops to get a Ca reading of 500 ppm. Can I shorten it down somewhat?


Premium Member
For calcium tests, you likely could do most of the drips in one shot, and then swirl the tube for 30 seconds or so. That works for the test kit that I use. I'd try a couple of tests, one a drop at a time, and the other with a mass dose :), and see how the results compare first, though.


New member
the amount of simultanious drops does not matter chemically, but for precision reasons they tell you to go drop by drop, adding to near where you think you are should be fine, unless you are mistaken.

and its only 15-20 drops man! just swirl it in the left hand and drop with the right, mixes as you drop.


New member
Yeah, but that requires coordination. I suppose if I dumped the water in a bucket instead of the test tube.....