# Help w/ Hagen Calcium Test Kit Pls



## aquasox (Sep 11, 2005)

When do I start counting the drops of reagent 3...do I count the total drops for step 5 only OR step 4 (1 drop) AND step 5 together?


Instructions read:

4) Add 1 drop of Reagent 3 to the test tube.......If, after 1 drop, the color changes from light pink to violet, the Ca measure is below 20 ppm.

5) If the color remains pink, continue to add 1 drop at a time....Count each drop and stop when color changes from light pink to violet....

6) Mulitply total number or drops by 20 to determine Ca ppm.


Thanks


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## dennis (Mar 1, 2004)

You include the first drop, technically.

According to the directions:
1drop=20ppm Ca
2drop=40
3drop=60
etc

That is not super accurate though and I would double the entire thing then divide by 2 to gat a more accurate reading. To do this, use a double sample of water (if the test says to use 10ml of tank water, use 20ml instead and add double any other initial reagents also). Then add your drops of reagent 3 and when the color changes to violet, multiply by 20 as per the directions then divide that by 2 to get a more accurate reading.


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## Edward (May 25, 2004)

Hi

- use 5 ml
- add 7 drops of reagent #1
- mix
- add 3 drops of reagent #2
- mix

- add 1st drop of reagent #3
- mix
- If color changed you have less then 20 ppm Ca, if not
add 2nd drop of reagebt #3
- If color changed you have 40 ppm Ca, if not
add 3rd drop &#8230;.and so on

[1 drop in 5 ml = 20 ppm Ca]
[1 drop in 10 ml = 10 ppm Ca]


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## dennis (Mar 1, 2004)

Sounds about right Edward


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