I use and like the Seachem test kit. As others have said, it's a titration
style kit meaning that you add drops until the colour changes. My experience
is that the colour change is rapid and distinct with this kit. Plus, the kit
supposedly lasts for 150 tests (I've only used it about 6 times so far). The
kit also comes with a standarized calcium solution so that you can test its
accuracy. I tried that, and it was bang on.

Don't know about the Salifert kit for calcium, but the Seachem has my vote.

Regards,

Dave.

"wolfhedd" wrote in message
nk.net...
i like saliferts, it works ok, but color charts always have a problem.
sound like salifert is your best bet however. it does the WHAM change
from
pink, to blueish, and it is assumed that the WHAM change it what is to be
assumed the measure point. others wonder if you keep dropping solution
until its totally clear blue, which in my opinion will give inaccurate
results. Im not sure about sea chems, but saliferts is GOOD.

wolfhedd

"Pszemol" wrote in message
...
"Pszemol" wrote in message
...
I am using SeaChem calcium test and they also use titrate method.


http://www.drsfostersmith.com/Produc...4397&N=1+11313
3&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.

Here you will find *.pdf file with complete, original instructions:
http://www.seachem.com/en_support/ki...40-Calcium.pdf