Great job Bruce !! Just be careful of that heater as Theo noted. Next week over wintered YP rule. By the way don't take any flash picts. in there --the reflection would be a killer.
ps If the window faces into the open end it may give you more light for your fish and may have some effect on the expir. if the intensity is to strong like a mirrow effect. Watch the glare on the water and see if it bothers the fish. ewest