I think Nicrew and Beamworks have a 6' LED option. Most other brands you will need to get 2 30/36" versions to go edge to edge. I am a fan of the Finnex LED 24/7 lights but may get an "Edge" to try as the Finnex remotes aren't that great.
Bought 10m led light strip from China Cost usd 15 16 colours 4 modes Remote control Able to custom cut on per meter basis 2 x nano air bubbles + 1 30l/min air pump Cost usd 25
www.monsterfishkeepers.com
This is the thread with the lighting... my tank has 2 holes at the top of each corner so I just put the led strip through them.... at the centre euro brace I use finishing line to hold them up....
Considering if to use suction cup to provide more holding power