I set out on this part of the project with a few ideas. I liked the idea of making the lighting canopy out of cedar to complement the rest of the aquarium, and thought something that looked a bit like a grape arbor might look good. I also wanted the light fixtures to have some means to be adjusted to fine tune the pitch of the reflectors to control the direction of the light.
We bought a bunch of cedar fence pickets that were on sale, and some 2x3's to fasten them to.
The pickets were about 6" wide, 1" thick and 6 feet long. I put them on the table saw and ripped them into uniform 2.5" strips which seemed more to scale with what we were building. I cut three 2x3 pieces to 24" in length figuring the canopy should be roughly the dimensions of the aquarium itself. Then I just nailed the pickets on top, using one as a spacer to leave gaps for air flow.
Once that was complete, I turned it over and test fit the reflectors, marking where the mounting holes for those would be. From this I decided where the eye-bolts should go. I realized that the boards were likely not strong enough to support the stress of the eye bolts alone, so I dug through our stock of assorted materials and found some pieces of metal left over from some shelving. I drilled holes in those and mounted the eye-bolts through them. This would cause the stress to be spread out through most of the exposed board on that side of the canopy. I would add some liquid nails later to keep the metal supports in place.
My idea for making the reflectors with adjustable pitch was to use these threaded fasteners shown on the right in the above photo. I would drill larger holes in the reflectors and insert these, then use the ring on the left to secure it to the reflector.
I would then insert these bolts through the wood in the canopy and thread them into the connectors on the reflectors. By turning the bolts from the top, I could draw each of the four connectors up or down and turn the reflector slightly in any direction. I also sketched out a similar system to bend the reflector sides inward to narrow the beam, but opted to wait and see if that is necessary.
To fasten the connectors to the reflectors I found these neat washer-like things that essentially slide on one-way. I found the best way to put them on is to set them over a hole drilled in a piece of wood as shown.
Then set the reflector over it, lining up the hole we drilled and setting the threaded connector in place. Then I used a scrap piece of wood to hold it in place while I delivered a couple blows to the wood piece to drive the connector into the washer below. The scrap wood prevented me from accidently hitting the reflector with the hammer. The connector on the left has been installed, the one on the right is ready to be installed.
Here you can see the connectors from the back side, ready to accept the bolts.
I drilled the holes and installed the bolts through the top. You can also see the eye bolts in place. Then I held the reflector in place and used an allen wrench to get all the bolts in place.
And here it is finally mounted. One bonus of this mounting method is that the reflector is set off from the wood which will promote cooling.