What is causing brown spots on the leaves on my peace lily? I don’t over...
From what I have been able to gather by doing a bit of research, Peace Lilies can be the ideal house plant, requiring very little light or watering. In fact, they should not be watered until the top inch or so of soil has dried out. Water can be another source of problems, because peace lilies are sensitive to fluoride in water, so you may want to consider using a water source other than your tap water. An extension specialist in Illinois discusses this: https://web.extension.illinois.edu/askextension/thisQuestion.cfm?ThreadID=23066&catID=31&Ask...
But the spots I see in your photo can be a symptom of a worse problem; they seem to indicate the presence of a fungal disease. I am sending links to some extensions service fact sheets that discuss this and the remedies for it. From Penn State: https://extension.psu.edu/spathiphyllum-diseases
A University of Florida guide for producers of this plant goes into more scientific detail: https://mrec.ifas.ufl.edu/Foliage/folnotes/spathiph.htm
f you are certain that the plant is getting no direct sunlight, and you have eliminated tap water as its water source, you may want to purchase a fungicide for tropical/house plants.