I'm sorry I'm not sure what that is. Drops are fine for ph as long as you stay on top of it.....knowing the color you want etc..and it seems to remain consistent in your readings. Updated pics wosuld help......you say a thermometer at the level the plants is reading 77 degrees? Looking at my own 400wmh I think my plants would melt at that so something is not making sense.....upturned edges are usually a sign of heat stress as well as Dutch first mentioned. I'm going to go measure my leaf temps right now. And yes, there is tempered glass as I have vented the 400w through the hood before....brb......