Thanks man...I appreciate the honest answer.What makes this hard is a lot of companies spit out numbers like they have a clue. I would be lying like everyone else if I gave an exact distance. The only way for an accurate distance is to try and read the plants. I usually go by 20-24” myself in flower. I also write things down. This way I can try and adjust before the same problem occurs again. There are just way to many variables to give a one height fits all.
I can say this...they freaking love the light. I'm running out of room; they are now within 18" of the light and my tent isn't going to be tall enough if this keeps up!