ok, but what is it by deffinition?a sump is wat i am getting soon
get this book i recommend it to every one getting into this hobby
Amazon.com: Used and New: The Conscientious Marine Aquarist: A Commonsense Handbook for Successful Saltwater Hobbyists
EDIT:
Best advice for a reef aquarium:
GO SLOW
This is not a hobby if you like instant results. It takes at least a year for your first tank to settle down and become truly stable enough to care for exotic corals and fish. Rushing through it so you can have a fully stocked reef is kinda cheating yourself IMO. You miss out on all the cool changes that happen as small corals in an immature tank grow and mature into a a truly beautiful world a year or two down the road. Also, buying large corals now only limits the available room for the ones you'll no doubt find more colorful and interesting/challenging in a year or two.