Abstract: A fluorescent illuminating device that mounts on a vertical side portion of an aquarium having a water resistant, rigid, vinyl housing with a vinyl woodgrain laminate 20 adhering to the back surface of the housing. The fixture can be mounted to any aquarium vertical side portion with a width of 12" or more. The fixture is mounted utilizing L-shaped securing hangers 12 that wedge between aquarium top frame element 10 and aquarium transparent surface 34. In addition, the securing hangers 12 wedge between channels 14A and rubber strips 14B positioned on the top surface of the housing. The L-shaped adhering braces 30A attach to the aquarium transparent surface 34 and attach to the bottom surface of the housing with screws 30C. This mounting configuration allows for the removal of the device by removing the screws 30C and pulling fixture out, perpendicular to aquarium transparent surface 34. The interior of the fixture has a reflecting surface 28C that primarily directs light diagonally into the aquarium.