It is a octopus. I am not sure of the model. Fits inside my 50 gallon sump. Only have some damsels in with them. I have a created a ledge our of pvc pipe and eggcrate with rock on top. The entire bottom of the tank is open, with just the pvc pipe, so they can swim around the entire bottom. My goal was always to raise them from babies and breed them. Now that they have layed eggs, I will be selling them in a few weeks. Later this summer I will sell the babies, and then the complete set up. Moving on to another hobby. I see you are from Zephyrhills, I am in Tampa, not too far if your interested in buying these sharks.