I have one over my 29, seems to do a pretty good job. I just took par readings on it the other day. At 100% all around I got a little over 100 at the bottom and about 270-300 just below the surface. My tank is doing well Zoas and LPS seem to love it. However I have not have much luck with many sps although I do have a few that are hanging in there. This could be due to other factors though and not just the light. Colors really pop but its a little spotty as are many led fixtures.