A freshwater aquarium is a receptacle that holds one or more freshwater aquatic organisms for decorative, pet-keeping, or research purposes. Modern aquariums are most often made from transparent glass or acrylic glass. Typical inhabitants include fish, plants, amphibians, and invertebrates, such as snails and crustaceans.
Tropical freshwater aquarium

Freshwater fish may be either coldwater or tropical species. Although freshwater aquariums can be set up as community tanks, coldwater and tropical fish are generally not mixed due to incompatibilities in temperature requirements. Coldwater aquariums house goldfish and other species that do not require a heating apparatus. Warmer temperatures would actually increase their metabolism and shorten their lifespan.[1] For a tropical fish tank, maintaining a warm environmental temperature ranging between 75 to 80 °F (24 to 27 °C) enables the fish to thrive.

Aquariums may be decorated with sand or gravel, live or plastic plants, driftwood, rocks, and a variety of commercially made plastic sculptures. The smallest aquariums are fish bowls, but these are not recommended for most fish as they are generally too small.