[philipraposo1982]

I never used this before. I want to test for kh. I am supposed to add one drop at a time and watch for the color to go from blue to yellow.

Where I fail to understand is, do they mean the slightest sign of yellow tint? Or do I need to match the yellow on the back as close at possible??

If you know please help.me test so I can have an accurate measurement. Thanks

 

[philipraposo1982]

Still leaving guessing as to what degree of yellow.

I can get a color change in about 3 drops. But its not a bright yellow like the card.