600 hps heat

My plants are about 6 inches from the bulb, will this be damaging yo the plant?

Because it's so hot in the tent, I have been watering them more, is this advisable? I think I nute burned them, the tops leaves are getting yellow and shriviling up.

I have also been spraying them a lot, are there any adverse affects to this?

Put your hand at the top of your plants for a minute. If you don't feel uncomfortable then it should be fine for the plants too assuming you have proper air movement.

Spraying your plants and then placing them so close under a hot lamp could easily cause the leaves to burn (think of the water droplets as tiny magnifying glasses). The top leaves are probably dying because of the intense heat under a 600w. Try keeping them about 18-24 inches away, unless you use a cooltube. Good luck!

Even with a cooltube and a high-cfm fan, 6" is WAY too close! Back 'em up to something like 14" to 20" away. I doubt your burn problem is nute-related. 10 to 1 it is just because of the heat from the lamp cooking your plants.