I noticed these rust spots on my leaves around day 6. This is a day 10 Seedling.
I am running aerogrow bounty with 1 plant before i move to a larger system.
Using GH Flora series PPM around 400 w/Cal-Mag & Hydro Guard
PH Between 5.8-6.0 (constant)
Grow room temp 75 with 45%-55% Humidity
I change the water 1 once a week and lights are 8-9 inch above plant (LED)