I never understood that either!

I've had plants burning like crazy when my nutes and "salts" were way out of hand. The bad tap water was compounding the problem. After getting ppm/EC under control the dang plants can touch the air cooled hood glass and just thrive. No signs of burning nor bleaching. Go figure.

Quote Originally Posted by Sprite
Here's the thing I don't quite understand about temperature: I read everywhere that 75 degrees or so is optimal. I also read that you can put your light real close and as long as your hand doesn't burn after a minute, your plants would be fine. So my hand can withstand temperatures way higher than 75 degrees! This seems like conflicting info--can anyone clarify?

Apologies if these seem like dumb questions. I have spent lots of time doing lots of research, but some stuff just doesn't seem to add up.