We appreciate your continued business with us and are sorry to hear about your experience with your Hanna salinity tester. However, we did see the full email exchange between you and Hanna, and no one from their team was rude to you. They were simply explaining that digital salinity testers use electrical conductivity to measure salinity, which will not give the same readings as a hydrometer or refractometer, since those rely on different measurement methods (specific gravity vs. conductivity-based salinity). The values can differ slightly, which is completely normal and expected.
That said, your response to them was extremely inappropriate and unacceptable. Using racist or abusive language, including telling someone to “go f*** yourself, you French piece of s***”, is never justified under any circumstance. This type of language is offensive, discriminatory, and goes far beyond expressing frustration.
We always encourage respectful communication, even when you disagree makes every interaction better for everyone involved.