Guys its obvious that I'm currently doing loads of research for my new tank. I found this into on Calcium Reactor that I found really handy.
You might want to have a lookie
http://www.reefkeeping.com/issues/2002-05/sh/feature/index.php
You might want to have a lookie
http://www.reefkeeping.com/issues/2002-05/sh/feature/index.php