Agree, if all the lights are reading the same, then I don't think it's a light issue. What's your photo period? I've always used a 12hr cycle with my Kessil's and a 6 to 8hr peak. Corals looks good, so I would judge everything on coral health and not numbers. There's another reefer here who uses five over a 90g (or something close to that) and he's rock'n corals without issue.