Asked October 13, 2021, 2:26 PM EDT
Dakota County Minnesota
Thank you for writing.
This is a very good description of this matter. https://homeguides.sfgate.com/dustylooking-mold-soil-houseplants-41109.html The mold is harmless, more of a symptom than a disease. Saprophytic is a generic term that means 'eating rotted material.'
The problem is most often related to a failure of the pot to drain water away rather than to the watering itself. The failure to drain can cause rotting of the roots which will stunt the plant and make it somewhat yellow. Root rot is described well here. https://www.gardeningknowhow.com/plant-problems/disease/treating-root-rot-gardening-tips-for-housplants.htm
I suggest you remove the plant, look for root rot, make sure that the pot drains to an under-dish, repot in fresh soil.