Ca Test kit problem

[leftme]

I am having trouble reading my Hagen Calcium test kit and I need help.
The colour change is suposed to go from pink to purple. I honestly can't see the colour change happen, I stop trying to get the test to work after my calcium reading would be over 800ppm.
To me the colour goes from pink to darker pink with various shades of pink in between. Any test kits that go from red to blue or something like that?

Clayton