HELP! What’s on these leaves?

It’s this brown Sticky stuff and the leaves are also yellow and crusting away at the edges. It’s not on all of the leaves just a few but it’s on multiple plants. They are in organic soil, 2.3 gallon pots watered with r.o. with tablespoon per gallon cal mag added. Under 400 watts led light,40 percent humidity. As far as bugs all I’ve seen is a minimal number of fungus gnats which don’t concern me.

Not every leaf is going to stay picture perfect. Its the top half of the plant to watch. She'll shed leaves. There will be ugly. It's the top half growth that matters the most.

Beehive said:

Not every leaf is going to stay picture perfect. Its the top half of the plant to watch. She'll shed leaves. There will be ugly. It's the top half growth that matters the most.

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Ok, cool thank you. I’m reassured because I thought it could be a mold or something and I need to flower them soon