I blog about salt water aquarium as everyone seems to love a  marine aquarium that  keeps marine plants and animals in a contained environment.
Interesting. What are the best fish to keep in a salt water aquarium?
I will just talk in general about an aquarium. You can find fish, invertebrates, amphibians, aquatic reptiles such as turtles, and aquatic plants in an aquarium
Cool. What type of people seem to most enjoy aquariums? 
Most times they are hobbyist and the categorized the aquarium to be  fish only (FO), fish only with live rock (FOWLR), and reef aquaria.
I see. Is it expensive to maintain an aquarium?
is different from its freshwater counterpart because of the fundamental differences in the constitution of saltwater and the resulting differences in the adaptation of its inhabitants. A stable marine aquarium requires more equipment than freshwater systems, and generally requires more stringent water quality monitoring. The inhabitants of a marine aquarium are often difficult to acquire and are usually more expensive than freshwater aquarium inhabitants.
Marine fishkeeping history.
The first saltwater tanks were Venetian glass jars where the Romans kept anemones outdoors, but these systems were very short lived.
The Aztec
Aquarium
An aquarium (plural: "aquariums" or "aquaria") is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aquatic reptiles such as turtles, and aquatic plants. The term "aquarium", coined by English naturalist Philip Henry Gosse, combines the Latin root "aqua", meaning water, with the suffix "-arium", meaning "a place for relating to".