I had no idea. THANKS for broadening my knowledge base.
Have plenty of room for more
Oh hes right.
But the issue is dosing. Do you want to dose? Are you confident enough in yourself to accurately measure, and dose everything? Magnesium? Alk? Calcium? Thats the major difference. We can argue until we are all blue in the face. IO is fine for most, its fine for those who want a great tank and don't mind dosing. But I want you to look at one VERY important fact. Who doses here, and who has had a tank CRASH. Not a little "oops", but a full on tank crash. Do a search. Its those who dose, and dose incorrectly, maintaining that perfect PH/Calcium/Alk/Mag that have crashes. They see incredible growth, until it blows up on them.
I prefer to do water changes with a quality salt, and not tinker with everything daily. As they said before, if its not broke don't fix it. But my SPS seem to like that fact that I do a simple weekly water change, and I don't have swings in my levels, because I don't dose. I add calcium on Wednesdays, and water changes on Saturdays. If I skip a water change, I add Iodide, and strontium. Never have I had an issue. I lose one SPS coral, due to bad flow and placement. But not water quality.
But to each his own.