I have 6 plants all affected by whatever this is, some much more than others. It seems to have started in all the oldest first fan leaves. Yellow spots that have spread to each of the lower leaves and now all my plants show small amounts. The new leaves are green but i have noticed that the dots are starting on some of the higher leaves. Over time almost all of my lower first single serrated leaves have pretty much died turning all yellow and brown. I waited way to long to address this sprayed my plants with Neem oil. Tried to make them more healthy couple weeks ago switched the soil started PH water, made sure to not over-water them.
Still do not know the cause.

Soil; Started with MG in nectar of the Gods
Nutes; Thought it could be deficiency been feeding them every other Nectar of the Gods
Rh: fluctuates between 30-50%
Temps: constant 68-71
PH; of water and feedings 6.0-6.4
light: LED looks like T5 puts off 3k lumens about 3" from top
Almost a month from Seed
up to their 5th-6th nodes each first and second sets of leaves are all about completely dead

These pics show the progression. The last one is a newer leaf starting to show signs. Middle is a lower starting to yellow. Last one is my first set of 3 serrated leaves pretty much dead, it wasnt even the worst one my other plants first serrated and 3 serrated sets are either all yellow or all brown.
I know its long i wanted to be thorough, appreciate any input from you guys