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Old 03-30-2011, 03:29 AM
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Quote:
Originally Posted by mark View Post
and another reason I don't like the drop count type.

how's the colour change though? Is it one colour to another, or change in shade of the same colour.
If you're asking about the seachem reef status tests, it's an unmistakeable change. I'm on my second Mg/alk test kit and I've noticed the indicator on the second one isn't as dark as the first, but I've been doing two drops instead of one and I luckily have some left from the first kit. The alk test is the difference between a sky blue and pale, almost colourless yellow, with a fairly dramatic colour change at the end point.

The MG test starts out a dark fuschia and turns dark purple at end point, and the calcium goes from a rose pink to a really pretty blue.

Because you dispense such tiny volumes of reagent with every drop, it's possible to get right up to the end point and not be sure if you've gone over, but in that case you just read the volume on the syringe before you add your second drop.
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