An average kreisel tank housing a number of moon jellyfish A kreisel tank (kreisel being German for "spinning prime" or "gyroscope") is definitely an aquarium shaped like a horizontal cylinder that is certainly designed to hold delicate animals for instance jellyfish and newborn seahorses. These aquariums offer gradual, circular water http://www.countrypwr.com/united-states/signal-hill/age-of-aquariums