Size of AI rail for 75 gal

[Volcmreefer]

I'm about ready to set up my 75 gallon reef and was wondering what size AI Rail I should use. The tank is 4 ft long and I have 2 lights. I want to hang them. Any suggestions? I am thinking a 6 inch rail, but unsure. Thanks and happy reefing!

 

[joeysreef]

I have a 75 gal and got the 12" ones

 

[joeysreef]

Oh but mine are on the ext tank mount not hanging from ceiling

 

[Volcmreefer]

Cool, thanks. I think that I want to hang mine. Anybody have some hanging over a 75?