>>29470622my history is with freshwater tanks, but i know there's a bit more upkeep with saltwater.
water quality and salinity levels require a bit more upkeep, but its not like you need a chemistry course to understand this stuff. prob helps though. you can go to a petco for stuff, but id strongly reccomend visiting a proper aquarium store for healthier fish and better knowledge.
i think the biggest thing to understand are habitats. things like tank size versus whats going in them, and who can get along with what. also maintaining a proper diet is key too, as well as water changes.
if you really want to try this, start with something small and simple. don't go out and buy a dirty 300gal off of craigslist with a big ass sump. get a 5gal and put something cheap in there.