| It can be a number of things.
The first I would check is if it is burn. Phals are low light level plants and burn easy. If they were in the sun for more than a couple of hours it is probably burn and should be moved to less light.
there are several bacterial infections from over watering that can start as brown spotting, but these usually spread rapidly and kill the plant fast.
I would check the lighting first.
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jerry  |