Overwatering is NOT too much water. Overwatering means you are watering too often. You should water your plants until water starts to come out the holes in the bottom of the pot, then let them dry out before watering agian. You should be watering about every 3 or 4 days so the soil can dry out inbetween. If you have to water you plants daily or even every second day, that means your pot is too small for the plant or you grow medium may need more vermiculite for water retention. If your plants are staying wet for too long you might want to use more perlite to help with water drainage.
I hope this helps.

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Hospitals have patience... I DON'T!!!