Question Hard water

Hello everyone I am having a tough time removing hard water spots from French pane windows. It seems that these windows were tinted on the outside which makes the traditional methods (I use scrub off from ettore and or scrape) ineffective any suggestions on what to use? I have tried vinegar and other water spot solutions but since the hard water is on the actual tint it's making me think that is why it is ineffective. Thanks in advance for any help

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