Hi everyone, thank you for taking a minute to read this and offering any insight.

I've recently discovered, what I suspect is a fungal issue with my seedlings. If you look at the picture, you'll notice lots of very tiny black dots on each leaf. These were organic seeds purchased from a reputable distributor, so I doubt it is from the seed.
The temperature is a constant 75F with a pad underneath and they are under four 4' ft 40Watt white fluorescent bulbs for 19 hours a day at a distance of 3 inches. I think I was slightly over watering them at first because they had leave roll, but that has gotten better. There about 3 weeks old. My guess is that it is a fungal issue, but before I look for a solution, I want certainty of the issue. Please, can anyone identify what this issue is. Is it a fungal issue, light, watering???

Please and thank you. Any advice is much appreciated.