Newbie to buy an existing old tank set up or start new???

[Aquattro]

Hi, welcome to Canreef! The first thing you need to do is decide what you want to keep in a marine setup. This will determine the requirements (cost) for setting up a system. A decent nano can probably be built for $500, or a good powerhead could also cost $500. Lighting is amajor cost in reef setups, and again, depending on what you want to keep, that could eat up a big chunk of your budget. There wasa thread a while ago about the costs of setting up a nano vs. larger systems; I'll try and find it for you.