most reefer avoid using UV on reef tanks because it kills a lot of micro life, which is natural food to support filter feeders. Reactors come in handy when you have a large bio load of coral, which need stable calcium to support porper growth, color, and health. Lighting is important as well. Skimmer are nice but not needed, same with a sump. Only reason why i would suggest not using anything else other then a sump is because you can incorperate a fuge, which will help remove nitrate and phosphate from the water which keeps the water healthy for fish and corals, and prevents unsightly algae from mostly growing in the display tank. For a tank of your size, id say get one and call it good.