White spot on fan leaves

i believe im having the same problem as the other guy who made this post and i just have a better picture of the problem. i am growing ice in a 2x4x10 space its a little crowded i have a fan providing good circulation. i am using 4 incandescent light bulbs that are 120 watts so 480 watts. i use regular tap water i live in san antonio water as needed. i dont know what the problem could be. im using "dutch master advance flower floraison" its a two part flowering solution.

thanks for any advice

Do you water with the lights on or off? And do you get water on the fan leaves or strickly to the soil? If your using tap water there are usually substances added like cholrine to make sure it sterile

i water with the lights on and i use to spray water on the leave but since i have entered the flowering cycle i have not sprayed the leaves with water at all. i usually just rub the white spot off with a dab of water on the leaf. i also usually leave the water out to help protect against chlorine and other added substances to tap water