Nance, the seedlings are closer together than I'd go for.
If too many seedlings germinate too close together it's really difficult to separate them without causing damage when potting-up,
as well as the tightly-packed plants reducing airflow.
They also look quite 'leggy' to me; are they getting plenty of bright light?
Aside from that, good drainage, aeration and allowing the medium to dry out a bit between waterings are the biggies for damping-off.
Growing for microgreens is not the same as what I thought you were trying to do.
CJ Verde showed a set up for that.
Think microgreens are always grown in a soiless mix.
You should be able to find lots of info on line as to how to do this.
Fodder systems are getting to be a big deal for feeding livestock.
Maybe you could get some ideas by checking out a site that sold those systems.
Your pictures show exactly what will happen if you try to grow microgreens without using proper techniques.
Thanks for your input. I grow many MICROGREENS in a soilless mix and have no damping off. Many MICROGREENS are still grown in a soilless mix. I am familiar with the fodder system, as well as many other ways to grow MICROGREENS . At this time it is to expensive for me to get involved with.
There are people doing fodder systems on the cheap. The pumps are cheap and it's not too hard to get cobble something together. I think there are some threads on this forum or here's another:
Dead simple fodder system
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