Reading Hagen GH/KH Test Kit.

[T8T]

I was wondering if I could get some help reading my results.

5ml of test water. Add one drop and shake. Blue color will be result.
Keep adding drops one at a time until the sample turns yellow. It takes me 10 drops to get there. So you multiply 10 x 10 and you get 100.
I'm lost from there.

[Aqua World Clif]

Hi there! I'm not sure exactly what your instructions say, but it sounds as though your water hardness is fairly soft...

Instead of explaining it to you, check out this website about water chemistry. It's all expliained out in (more-or-less) layman's terms.

The URL is: Beginner FAQ: Water Chemistry.

Enjoy!
~ Clifton

[jpmorley]

You are measuring carbonate hardness (KH). Carbonate is what causes your water to be alkaline and you need alkalinity. The color change occurs when one of your reagents, an acid, has neutralized all the alkalinity. The important thing is that your KH should, according to the experts, be in the range 105-125. Since you are just a bit low, you should get a carbonate buffer to add to your water... although at 100 you really don't have a problem. These kits are usually only accurate to one drop or + or - 10 on the KH scale. You may actually have a KH of 110. If the solution starts to go yellow and then changes partly back to blue (i.e. greenish yellow) you need to add one more drop. If your pH is and remains OK, I would find something more important to worry about. Good luck.