From these tests, the PFO Parallel reflectors seem to reflect more than the Optimal:
http://www.advancedaquarist.com/issu...03/feature.htm
Code:
Distance Light incident Light incident Light incident Max
3 X 3 Area 2 X 2 Area 1 X 1 Area PAR
PFO Parallel
6” 47,415 44,495 33,313 3,062
9” 42,449 37,603 23,052 1,599
12” 38,238 30,702 15,962 829
PFO Perpendicular
6” 41,810 39,179 27,456 2,070
9” 39,213 33,212 18,871 1,066
12” 35,456 27,573 13,185 809