Salifert Calcium test Aqua blue, usually dark blue??

[Flipper_Picker]

I started dosing kalkwasser recently and after testing parameters today, the color is off on my Salifert Calcium Pro test kit. The color is Aqua blue when it's usually dark blue. The colored changed from pink to aqua blue around 460 ppm. I tested twice using different syringes/containers and the results were the same. Also my PH is lower than normal, not sure why. I don't use 2 part or anything, just Kalkwasser. Also, I tried adding more than 1 ml of the "C" solution to see if it would change to dark blue but it didn't get any darker. Has anyone ever seen this light blue color when using salifert calcium test kit?

Alk 10.1
Ph 8.1
Calcium 460

 

[Ron Reefman]

Mine is always light blue. I've never seen it dark blue.

 

[fish farmer]

Looks like the Red Sea Pro kit.

My Salifert Calcium kit seems to turn lighter blue when it is nearing its expiration date.