live sand and live rock have the beneficial bacteria and stuff like that living in it. They are both good for a tank. All you have to do to care for it is just keep the water clean and in the right water parameters. The rocks are good if you have a bunch of it because it creates hiding spaces for the fish which makes them feel safe. And when the fish feel happy and safe there is less of a chance for diseases like ich. Now not all the rock going in the tank has to be live. You can mix live rock with dead rock. All the dead stuff will become live over time when the bacteria grows on it.
Protein skimmers are good for a tank your size. They will help to take out the nasty stuff in your water like waste and stuff.
Protein skimmers are good for a tank your size. They will help to take out the nasty stuff in your water like waste and stuff.