Hey guys, I'm on my phone and the search function doesn't seem to be working, so I apologize if this is rehashing a previous post. I have had fresh water aquariums for a while. (Several years before I was married and this last year as well.) I want to set up a reef tank. I don't want a FOWLR. I have a 75 gallon tank with a 29 gallon that will fit inside the stand to make into a sump. I know almost nothing about marine tanks, but I do know how to research and answer specific questions. That being said, my question is this. What is something you wish you had known when you started your first marine tank?