We cleaned the windows for a lovely couple in Naples, FL last week and they had a salt water pool with a small inlet near bay windows with 3 fountains. These fountains were splashing the large bay windows. When Jon tried cleaning them with our usual mix of Dawn and rainex they wouldn't foam up and the water marks wouldn't come off.
It wasn't until after that the customer told us about the salt water pool. She has already had to have the window buffed. Is there anything that would get these marks off?