A saltwater tank is an aquarium designed to hold marine life, such as fish, corals, and invertebrates, in a saltwater environment. This type of tank requires specific equipment, including a filtration system, heater, and lighting, to maintain the proper conditions for the organisms. The water in a saltwater tank is typically mixed with sea salt to achieve the right salinity levels. Maintaining a saltwater tank can be more complex than a freshwater aquarium due to the needs of the marine species. Regular testing of water parameters, such as pH and salinity, is essential for the health of the inhabitants. Popular choices for saltwater fish include species like clownfish and tangs, while live rock is often used to provide habitat and promote beneficial bacteria.