Dry Mildew

I have dry mildew on my babies and need a remedy I can seem to remember the one that a friend of mine had told me

Piss on em

Lots of air flow and spray her down with a watered down solution of hydrogen peroxide.

Not sure if we're talking about the same thing. I had a seedling that appeared to have a dry, white
powdery look to it and was not growing well. Used 10/1 mix of water and milk and a que-tip to
wipe the leaves with. Lil girl is doing fine now, new growth is strong and looking normal.
The affected leaves survived but did not recover from the damage.

Hope this helps, Good Luck

I had a tiny bit of this myself, spraying the leaves as galvatron said fixed it pretty quick