BROWN SPOTS AND PATCHES SOMONE HELp!!

There are brown spots on the seedlings (on the younger sprout leaves) and big patches...they are about 2 1/2 weeks old and the second set of normal looking leaves are coming in..whats the cause is it burning, is my light to close? is it nute burn(not using nutrients at this moment) Personally i was thinking it could be the bowl of water i was putting in the space (it was tap water than hasn't been sitting out to get all the chlorine out of it) i was thinking that all the chemicals evaporating from the water were burning it but i have no clue...The temp is 82 degrees and the humidity is 51% the ligh i says is about 4 inches away from the canope( i had to move it cause of burning,..just in case you know)I have the light schedule on 24 hours on...should i change my schedule to 18/6? so it wont be under the constant light to burn it. i just need help...well anyways if anyone has feedback I NEED IT BAD!!!!!

What light are you using and also what soil?

150 watt replacement cfl and the soil...signature master gardener al purpose potting soil + bone meal and it got sand and perlite in it and shit

anyone wanna help?

could be the result of a few things..
1. Manganese Deficiency ...cure = epsom salt..you can get at wal-mart its in the bath section..it says on the box how to apply to plants too
2) if you have blobs of water on leaves after watering it can act like a magnifying lense and burn from the light
3) are u ph testing your water?

hope this helps

Isn't epsom salt magnesium NOT manganese Sulfate.