Habitat lighting assembly

An aquarium lighting assembly, comprising:

• an outer housing configured to be positioned proximate an aquarium for directing light into the aquarium and including a base with a light-transmissive opening;
• a light guide contained in the outer housing and positioned over the light-transmissive opening, the light guide comprising opposite first and second major surfaces and at least one edge surface extending between the first and second major surfaces;
• a solid-state light source contained in the outer housing and arranged to emit light into the at least one edge surface of the light guide;
• a plurality of integrated optical elements associated with the first major surface and configured to redirect the light emitted by the solid-state light source, the integrated optical elements comprising three-dimensional structures extending into or out of the first major surface;
• and
• a heat transfer system configured to transfer heat generated by the solid-state lighting source away from the light guide.