Thanks so much for all your work on this. I just got the Apex PMK yesterday. All my PAR numbers seemed really low. My tank is two years old and I have what I think is pretty good growth. At least nothing is dying. I was getting a reading of 80 PAR 18" under two Kessil A360s at 70% intensity and 50% color. That just didn't seem right. If I add your correct factor of 30 PAR that seems much closer to what Ryan got in his testing. If I had read your post before buying the PMK, I probably would have waited.