What we're you trying to build your canopy out of? Also you're going to either hang with wire cable from ceiling or mount directly to the wall. I mounted my flatting canopy directly into the wall and made it light enough that it would not need much. Screwing into a stud would he your best bet as well fixing up small screw holes if you ever take it down are very doable. I have an open top floating canopy and built wood bracket's that my light bar rests on.
I'm going to build essentially what you built. I looked around today at possible solutions and it's costly either way you go. So this afternoon I bought a nice compound miter saw and picked up some 12" PVC boards along with 2" and 4" to construct the canopy. I'm still not sure what I'll use on top if anything but am definitely not sure how I'll hang it. I looked for over an hour today at Lowe's and HD and just couldn't decide on a solution. I can't imagine it will weigh more than fifty pounds but my soffit above the tank isn't really built strong enough to support it. I've been trying to figure out a way to wall mount it but I have to come off the wall 7" for the canopy to look right. I know I'm way over thinking this but just want it right. The tanks right next to my couch in my living room so I'll be seeing it every night. Any ideas are welcome and nice job with your setup.