I run two marine tanks and starting a fresh planted tank as well...The larger the marine tank the easier to maintain (not easy just easier) in keeping parameters...As mentioned above, reef tanks and fish only tanks have different parameters. You need live rock or a refugium (sp) (or both)..An RO/DO is a necessity..But the good thig about evaporation is you just need to replace the water, the salt does not evaporate..You may also need a chiller as corals have no tolerance for temp. changes...A good battery backup is also needed for power outages... Im far from expert but may be able to help you not spend sooo much money making mistakes that I did..!!