Careful.. about how much you are watering and feeding... this is another reason to add perlite to soil mixtures.. so that if something does go wrong you can flush without the worry of over watering

Do you have fans blowing the heat away from your plants?

How does your hand feel when you leave it at the same distant from the light as the tops of your plants?

FLushing is basically running as much watre though your medium as possible to dilute the nutrient/salt build up...

Make sure your FLUSH water is PHed properly! 6.8

good luck BOB.. i am rooting for you...