General advice on saltwater tanks:
water for waterchanges if you plan to keep corals. Topoffs with RODI
If you plan to keep corals, buy a powerfull reef lighting system.
Protein skimmer is cool.
Always ask the forum before buying livestock :p
You probably already know about the nitrogen cycle... This is the same in SW
Salinity must be kept between 1.020 and 1.025. Never add salt directly to the tank. Temp between 25.5C° and 27.5C°.
Thoses params are optimal but not necessary: Mg
: 1400, Ca
: 440, Kh
You will need powerheads for the waterflow. Make sure there's a lot of surface agitation. You need live rocks.
Before buying LR
or livestock, learn about diseases and parasites.