Well, they've been in about half that so far, and this plant wasn't looking wonderful, but was recovering well. The lucas formula calls for 7g at this phase, but I'm not sure if the mbferts stuff I added is causing problems. I may just try a res fill with water and hydroguard for a day or two and let it soak up some clean water before reintroducing nutes. I'm not positive what I'm dealing with here, the other tent I have is identical, same lights, plants the same distance below, and they don't even show minor signs of heat stress.