rush
Aquarium Advice Freak
If you are going to have corals a skimmer is an absolute MUST have. Now your sump does not need baffles, I have mine running without separations and its just fine. However, you will need a skimmer. I have mine with the skimmer on the left with macro algae, 35lbs of LR in the middle, and my return pump on the right hand side. I also have a sock filter for my overflow. Works great without baffles. It is your call though. Some people use them some dont.