I did not see the pictures but you seem to be describing powdey mildew or foliar mealy bug.

If these are big white puffy things, they are nests of foliar mealy bug. Take a Que Tip with rubbing alcohol and scrape off the nests.

If this is a powdery substance, You can put a tablespoon of milk in a cup of warm water and pour over the leaves. Do not rinse off until the following day.

I tried to see your pictures but could not get them.

Nancy

Hello Nancy,
thanks for the reply. I looked up images of powdery mildew and yes it seems like that is what it is. I will surely try the milk treatment and wait to see how they are doing. I am also going to isolate the infected plants and increase spacing and air circulation. I think maybe I have crammed too many small plants on one shelf.
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