Well go as big as you can afford, always research first before you buy anything, make sure to buy qaulity name brand equipment fisrt time so you dont need to buy the item twice and go SLOW!!!! Will you be building a canopy or will you be needing a light fixture and what do you plan to keep in the way of corals. I will say you need test kits and dont dose anything if you are not testing for it and IMO dont waste your money on purple up for coraline algea. Let us know what you want to do and we can give some ideas on equipment. OH and welcome to the addiction :D