Once you start saltwater you won't go back we went from 20 to 35 to 55 to 75. They are all up and running. All this in 5 months
Just starting a 8 gal
biocube for reef. My husband and I joke that we need to go to AA. Aquarists anonymous.
Let the tank cycle for 4 weeks. Only add 1-2 fish at a time. Before adding more make sure your levels are good. You will get diatom on your sand bed (brown algae) it can be there for a few months, continue to clean the sand at your weekly water changes. The sump, protein skimmer and other bells and whistles are expensive. I suggest them. But if you don't want them just make sure to check your levels often.
Good luck and welcome!