sentences:  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, tend to stunt fish growth, and may lead to eventual death.The earliest known aquariums were artificial fish ponds constructed by the ancient Sumerians over 4500 years ago.