What I see in those pics is a classic case of "I spilled nutrients on my leaves and put it back under the lights to burn spots on them" and I bet you're only watering a little at a time too, which will cause a salinity build up in your soil and lock out everything else, try having about 10% to 20% runoff when you water, that way you push out the old and let the new do it's job.
I get spots sometimes on my bottom leaves too from spillage, but usually a deficiency comes from not watering/feeding proper and/or not transplanting when needed