People have been keeping salt water tropical fish for centuries, but the technologies for keeping them have changed quite a bit over the years. The earliest type of salt water tank was the simple glass jar that the Romans used, and for centuries the technology didn't really change much. It wasn't until the 1950s that salt water aquarium fish technologies really took off, and the basic 20 gallon tanks that people still use were developed. Now anyone can have a beautiful marine aquarium in their home. In the early days of salt water aquarium fish keeping, the most popular type of salt water fish was probably the clownfish. People also enjoyed sergeant major damselfish, small pufferfish, scats, jeweled blennies and blue damsels. The water itself was actually collected from the ocean, which usually limited the hobby to people in coastal areas.
This was also problematic because unwanted organisms and pollutants came along with the water, which did not help the salt water tropical fish. Later in the salt water aquarium fish hobby, air driven, counter-current protein skimmers were invented and revolutionized in Germany along with the Eheim pump company. Perhaps the largest revolution in fish-keeping was a more reliable type of salt water submersible electric heater, invented by Eugen Jäger. The Jäger Company is still a major name in aquarium heating to this day. People have also realized over the years that algae and certain other bacteria are beneficial to salt water tropical fish, while sterile tanks with bleached corals used to be the norm.
