you don't need a refugium. it's just another component that helps clean the water. you also don't need GFO
, bio pellets, media reactors, controllers. those things just may or may not make your experience easier.
you will want to add the rock and sand, then cycle the tank. you will need an ammonia source. usually, uncured live rock has enough die off on it to start a cycle, but if not, many people have had success tossing in a raw cocktail shrimp and letting that rot in the tank for a little while to raise ammonia levels. then you wait it out. i would say about 3 weeks to a month, and you are ready for livestock.
you can add corals as soon as the cycle is over.
you will need strong lighting for corals. mushrooms and zoanthids generally are moderate lighting corals, but any stony corals/clams/anemones will need stronger lighting. i listed what you should use on the previous page. a 2 lamp t-5 fixture will not do.
also, use a reef grade salt mix. this should be closer to natural sea water and will allow you to keep a moderate amount of corals with just weekly water changes. every element you need in the water to keep photosynthetic corals is right in the salt mix.