White calcium looking stuff on my glass

[fla. keys]

Hello,
Please Help Me.
Other than using a razor blade how can i get off this white film off my glass. I tried using a credit card but it is like a milky white film I guess from kalk or this argonite milk stuff I have been using?
Help.

 

[desertreefer]

From the sound of it, you are using way too much Kalk, When you add Kalk, you should only add it to the Top-Off fresh water for your tank. If not, the calcium will float around in your tank and adhere to anything it comes in contact with, including your glass.