From what I have read and what others have told me, roots like temps around 72, but mine are like yours near 68... been trying to get my temps all dialed in for the next run, but have not gotten there yet. A narrow band when I keep the room around 75... night temps is what gets me thinking that I need to raise them some to keep the root temp up... thinking I need to get a data logger Temp/Humidity sensor in the root area to try to dial it in without raising canopy temp too much.