What kind of corals are you interested in? I ask this question as different types of corals will have different lighting requirments. For example softies will take less light on average than SPS
corals and Clams would be at the top of the lighting piramid when it comes to need.
Another thing to ask is do you like the ripple effect that MH
A good all around lighting setup for a 30 gal
reef would be one or two MH
bulbs and then a VHO
actinic to supplment. The number of MH
is somewhat dependant on ifyou have a center brace or not. If you do then you cant put a single MH
bulb ovefr the middle as the brace would cast a nasty shadow. If you dont have a center brace then you could put 1 MH
bulb over the middle but the side edges might be slightly shadowed as compaired to the middle.
For filtration most of us just use a sand bed, live rock and a skimmer. Adding a refuguium will also benifit your tank but is not needed. As for water flow start with a goal of 300-450GPH in the tank itself.