It is a 29 Gallon Bio Cube w/ 10 Blue leg crab, 10 turbo snails, 10 red leg crabs for clean up. Fish - 1 mandrin Goby, One Yellow tail wrasse, two Percula clowns, Mushrooms, Bubble tip, yellow poylps, and a green goniopora
Nice rockwork, looking good, is this your first tank? Yes, take the Mandarin back ASAP they need pods to survive and it will be amazing if it survives without starving. I would also drop some pellet food to the bottom for the crabs to eat, as the tank has no real food for that many cleanup crew.