I wouldn't really suggest buying a 6045 for a 75 reef. You would be better off looking at the 6055 (but more $$$) or the full sized streams for an aquarium of that size. The 6045 is really only designed for tanks up to 53 gallons.
Scott is a great vendor and as stated above he takes good care of MR people. You won't be sorry if you buy from him. Also I agree, these nano streams are really for smaller sized tanks needing alot of circulation. for a 75 I would buy either a regular stream or the biggest nano they make.