i have a 20 gallon tank (empty) that i would like to turn into a reef tank. i have experience helping out with a friends reef so i am good on most of the knowledge, but i would like some setup help. i wouldnt (if possible) like to have to plumb the tank as it is not drilled and an overflow box in a 20 gallon tank takes up WAY too much space. what exactly do i need and are there any options for not plumbing the tank and having a sump to be able to sustain a reef?