Do I NEED to add anything to my water?
 

I have a 33gallon with softies and a few LPS. Do I need to add anything? I've read a bit about calcium, trace elements, phytoplankton? I'd like to keep things simple...but I want everything to be healthy too. I also have a green open brain...do I need to feed him?

You'll only know if you need to add if you test and find low.

I don't worry about trace as hoping the salt mix and water changes will keep those up, but do check for Ca/Mg/Alk and found the salt mix can be low in these right from the pail (at least for IO).

article an trace elements
http://reefkeeping.com/issues/2007-04/rhf/index.php

great article on trace elements...thanks. What about feeding the corals? The open brain in particular