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View Full Version : elos expert line calcium test kit problem


aqua666
02/09/2010, 02:24 PM
I bought an Elos calcium test kit and the instructions for precise measurement says, add 7 drops of reagent A to 5 ml of water from tank and add a small amount of the powder B and mix. then add drops of reagent C less than the approximate measurement and then add drops of reagent D until the solution turns blue. multiply the number of drops from reagent c by 50 and the number of drops from reagent D by 10 and add them together.
it gives an example:
8 drops of C=450 mg/lt calcium + 5 drops reagent D=50 mg/lt. calcium concentration = 425 mg/lt

the problem is 8 multiplied by 50 is not 400 mg/lt not 450 and if you add 450 and 50 it gives you 500 mg/lt.
im wondering if the example is wrong or im doing some thing wrong.

shouldn't it be 8 drops of C=400mg/lt + drops reagent D=50 mg/lt. calcium concentration = 450 mg/lt?
where did 425 come from?

I would like to know how every one else using this kit measure their calcium.
thanks

GlassReef
02/09/2010, 03:43 PM
The example that comes with the kit is wrong.

luther1200
02/09/2010, 03:56 PM
Are you kidding, all that for a simple Ca test?

bertoni
02/09/2010, 04:24 PM
Oh, sigh, that does seem a bit complicated, but the Elos kits seem to get good reviews for accuracy. I haven't used that kit, so I can't help much. I think Elos might have a forum on RC where you might get some help.

JamesJR
02/09/2010, 04:47 PM
So far I have not been pleased with elos test kits. I got a magnesium kit the other day and the instructions were very hard to follow and very poorly written. I generally don't like test kits that require you to count drops as that seems to give very poor precision.

bertoni
02/09/2010, 05:25 PM
I hate counting drops, because I'm lazy and I forget the count. :) Oh, well.

Billybeau1
02/09/2010, 06:37 PM
If you do not like counting drops then you should just quit testing. Even the next level up from hobby grade which costs hundreds of dollars requires drop counting.

I know someone else who doesn't like counting drops.

Hi Randy. :wavehand:

Oil_Fan
02/09/2010, 09:52 PM
I don't have an Elos CA test kit handy but I did use it for a while. From what I recall, the first part of the test is to obtain an approximate reading. When the liquid changes to blue, you take note of the number of drops you used. You then redo the test using one less drop of the x50 liquid. From there you use x10 liquid to get a proper reading.

For example if it's still pink at 8 drops but turns blue at 9. That would give you an approx reading of 450. So you then redo the test using 8 drops. It should still be pinkish. Then start adding the x10 solution counting the drops. If you add 2 and then it turns blue, you'd take the 400 reading from the 8 drops of the x50 solution. Then add the number of drops from the x10 reading of 2 drops for an additional 20 ppm for a total of 420 ppm of CA.

BTW, their MG test is even more convoluted than their CA test!!

Randy Holmes-Farley
02/10/2010, 06:58 AM
If you do not like counting drops then you should just quit testing.

Music to my ears. :D