You have a great setup already! But yes, you do need to look at adding things. As for substrate, it can be sand or gravel it doesn't really matter. Do however make sure that it is "live" substrate. If I were you, I would look at adding more rock. You should have 1.5-2 lbs per gallon. When it comes to water circulation, I would suggest you bump it up big time. Look at the korailia series by Hydor. These pumps will work great. I would get at least two of them. Lighting is so key and unfortunates you might have to loosen your wallet a bit for it. I suggest either t5-ho
lighting or metal halide, or both. Try to achieve 5-7 watts per gallon on your lighting. Use majority white light. As for ro
, look at standard water filters. You can find them at Menards, Homedepot, or just about any hardware store. Get a standard canister. I use two canisters. One canister has a five micron carbon filter and the second has a .5-1 micron carbon filter. I am going to add di
canister and use standard color-changing di
media. The canisters run about $20-30 each and often times include the filter with them. Buying these is not as efficient as an ro
system but it is a lot cheaper and it does the job. Another upside to this is that you don't have to wait hours just to get a few gallons of water. When you have a tank my size you don't have the patience to wait that long for 10-15 gallons of water.
Hope this helps! Feel free to ask me anything about my reef tank. (210 gallons) I will help in anyway I can!