I'm not sure. I found this on another forum.
One of the latest tests I ran with my PAR meter on the IT2080 (32" fixture) and Radion Pro on the same tank, puts PAR numbers nearly identical. 30" down from fixture to the sandbed, both lights hit around 350 PAR (μmol m-2 s-1) at the sandbed dead center. Both hit around 1000 at the water line 8" down from the fixture.
Sent from my iPad using Tapatalk HD