What the hell?!?!?! appeared overnight!

hi all, i'm 6 or 7 weeks into flowering. I've been watering with spring water only for 6 days. I watered them yesterday and this morning this stuff appeared on my leaves! what's going on? i did make the mistake of letting this one go w/out water a day too long.
prior i was using PB bloom, earthjuice microjuice, liquid karma, and cal-mag.

Oh DAMN you got bugs from the looks of things!

i dont think so, i looked under the leaves and on them with a magnifying lens and found nothing.