I do keep an eye on it. Most of my soils are covered by coconut coir (fiber) or pebbles. The biggest cause of mold on houseplant soil is overwatering. After 60 years of raising them, I do not rely on my finger or a schedule for watering. I still use a moisture probe to test each pot and only give it water according to the plant's needs. In winter, many of my larger plants only get a drink every 2-3 weeks.
Another thing I do is (masked and gloved) remove the top inch or 2 of soil in each pot & replace with sterile potting soil each Fall (when the big pots come inside from the patio) or repot as needed - again sterile potting soil.
Since I learned not to overwater, I haven't had issues.
Sue

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