I heard that milk products should not be consumed with fish. I am not sure about the authenticity of this claim. Can you please enlighten me on the Islamic perspective of this?

There is nothing in Sharia about that, but experiments prove that drinking milk only without the rest of the dairy products such as laban and yogurt, or eating foods containing milk such as sweets, with fish causes health problems such as diarrhea, and may cause skin problems as well.