The most common aquarium sizes fall under the standard category. These consist of aquarium tanks ranging in sizes from 10 gallons to 100 gallons and up. These tanks offer a large amount of room for creating larger than life aquascape layouts. Common fauna choices are large schools of nano fish, smaller Cichlids, Gouramis, Angel fish, Discus and other medium sized tank inhabitants. Slightly on the larger size, they are a great canvas for unique nature aquariums.