Congratulations on a fine tank build, can't wait to see this baby up and running and the performance of the LEDS spots you're utilising.
If I could offer one piece of advice.....the hooks holding your light fixture looks a bit weak, it's possible these light weight hooks could pull out. While 4 of them might be OK with the chains vertically placed, the chains at 45 deg will be placing a lot of load on them.
If a central beam is your only option, I would drill holes and use hooks that go all the way through the timber, with a nut / washer arrangement for safe keeping.
Good luck in setting up this awesome display, love the coast to coast overflow, are you planning a bean animal overflow set up?
MTG IS A NOOB AND A 22 YEAR OLD SMART ARSE. HENCE WHY I WILL NO LONGER BE ON THIS FORUM HE ASSISTED IN CREATING. I'LL BE ON RTAW IF ANYONE NEEDS ME. GOOD LUCK WITH YA WEBSITE DICKHEAD, ALREADY KNOW A LOT OF REEFERS YOU HAVE SAID SHIT TO SMARTARSE. GOOD LUCK WITH YA WEBSIITE< NOT GOODLUCK WITH MY CORALS CUNT.