Your Monstera soil might be the problem , Even with perfect light & watering, a wrong mix can slowly damage your plant , Here are common soil mix mistakes to avoid , Using heavy garden soil, You can reuse potting soil How do I make a good soil mix out of these materials? : r succulents Ecoworm Soil Extract Concentrate Organic Vermicompost Fertilizer for Fruits & Vegetables 35 fl oz (Makes 53 gallons)