Brown/red spots on ends of leaves, leaves curling upwards

I looked through the guide but didn't find anything about red spots. I guess they're sort of copper colored. One leaf at the bottom got them real bad and has started to curl upwards, and a couple of other leaves are starting to get red at the tips too. It's doing really well regardless, but I'm still worried.

EDIT: I have a 400W MH light system about 2 feet above it, is that too close maybe?

Bump. I think I may have watered with nutrients too early, is that possible? It was hardly any, and I've flushed a couple of times, and not all the leaves are affected...any ideas?

What kind of soil are you using? what kind of nutes did you give? Lots of info missin there.

As for light distance that not an issue you should be able to even drop it at least a half a foot.

Soil is MiracleGro potting mix, I've used it before and never had problems. I used MiracleGro all-purpose plant food, .125 ml or .25 tsp diluted with a solo cup full of water, so it was very little.

Do you have a ph meter? Test your water before you water your plant then test your run off. see if the ph is to high. After that I'd check into some better nutes. I've got a friend that uses MG ferts and he said he had all kinds of burning issues.

nute burn, flush plant with 2-3 times the pots volume with ph corrected water.

This is what i would say to anyone who is Not Useing MG potting mix.
Does the potting mix come with slow release fertilizer already in it?
If so Flushing the plant May make the problem worse. as these types of potting mixes will release More Fertilizer when in contact with water.

Okay I think I got it under control, the leaves that were already burned look pretty bad but it's stopped spreading, I just flushed it good. Thanks a bunch guys