Recommended Water Parameters (Saltwater)

A common and important beginner question is "What are the ideal water parameters for my saltwater aquarium?"

And while you could just simply give a range, it' a bit more complex than that. There are three really important caveats that must be understood before talking about the ideal water parameters. That's because a beginner may just blindly do whatever it takes to achieve those ideals, even to the detriment of their pets. So what are those three caveats, and what are the ideal water parameters for saltwater aquariums... here we go!