Leaves are turning brown from the center with pictures. Please help

A week ago I sprayed my plants with some GoGnats. The following day, I mist my plants. Then a few hours later I started to notice brown spots. I assumed that I might have used a high concentrate of GoGnats. But, a week later and the leaves are still curling, spotting and dying. The leaves are dying from the center of the leaves where the leaves branch off.

Does anyone know what this problem might be?

when you spray anything on your plants make shore your lights are off. the water or any spray thats on your leaves will act like a magnifine glass and burn your plants I just made this mistake a week ago and found out the hard way. A indoor plant store told me about this. And make shore your PH is good becaause this can burn your leaves to but your plant should be alright.

I mist my plants when the lights are on and off. I do it more when it's on then off. Never had a problem. Thats why I thought it was the GoGnats. I think my ph has been climbing up a little lately. I need to bring it back down a little. Thanks for the help.

You shouldn't dismiss his advice. Spraying plants under a running HID light will likely burn them.

Oh sorry. I didn't mean I was dismissing his advice. I was just trying to say that I used to do it with no problem. I try to do it when lights are out but I just don't have time.

Well what sort of light have you got running?

It first occurred when I had a few cfl's. I have moved them into a larger room running a 600 watt mh light roughly 1 1/2feet away from the tops of the plants.

Here is an updated pictures. This is the same leaf in the picture as the very first one in the original post.

Thanks for any help.