A connecting bracket is disclosed which includes a base having first and second edges aligned at an angle to one another. A first member extends up from the first edge and a second member extends up from the second edge. Each of the first and second members has an end wall. A first tongue projects outward from the end wall of the first member and a second tongue projects outward from the end wall of the second member. The first and second tongues are designed to engage two frame members. Three or more frame members can be joined together in this fashion to form a frame assembly. A pair of frame assemblies can be used to secure at least three sidewalls of a structure to form an aquarium.
