A pet shop aquarium that gets completely out of hand. Drag one fish onto its twin and the two become the next fish up, which earns more than both of them did and gives you the spot back. Every fish in the tank pays you by the second, because the shop charges twenty cents to come and look, so the only real question is whether this coin buys another guppy or buys more tank to put guppies in. Four minutes to closing time, ten fish on the ladder, and the last one does not fit in the room.