That AquaEl tank/light combination could be from medium to high light, depending on how good the reflector(s) are, and how good the ballast is. I have never seen one, and there are no detail photos of the light in that website that I noticed, so I can't say any more about it.
I am looking to carpet my 20 gallon tall with Sagittaria requiring medium light. With a lighting system with a PAR of approximatly 105 at 6inchs, 45 at 12 inches, and 22 at 18 inches. Would this meet that lighting requirement?