Help!! my baby clone has weird spots

ok i attached some photos that might help im running a 400watt fluorescent light i have a little heater with a fan i just put the heater today so it shouldnt be that so...i checked for bugs well i usually check everyday since im home all the time now and ya no bugs from what i see...HELP ME PLEASE!!!! o ya just for people to know im using sensi grow ab with motherearth grow i use the 300ppm for of a and b of the sensi which is about .69 teaspoons and a 1/4 teaspoon of the motherearth for every quart. sooooooooo yaaaaa im so baked right now i just want my plants to be healthy o and i started using osmosis water from those machines outside of grocery stores...the guy at the hydro store said i shouldnt really worry about ppm that much cus osmosis water is like 0ppm so ya coooool...he said the pH is more important i dunno any hints suggestions are VERY APPRESHIATED!!! lol thanks u guys! toak up

spider mites?

the white spots look like spider mites. Look on the underside of the leaves for them

Hard to tell, but my guess would be mites. Or if you are spraying them then possibly focal burn from the light hitting drops of water on the leaves.

I agree the white spots look like mites but the brown spots are the start of a Calcium problem, and thats to be expected using RO water, either use tap water or your going to have to go out and buy Cal-Mag to add back in the good stuff the RO takes out.

Not dissing RO water, I use it myself, but if you dont have Cal-Mag its doing more bad that good.