I just bought some self watering planting pots with wicks for my African violets. Aside from needing to experiment with different sizes of wicks, my main question is: does the reservoir need to run empty of water before refilling, or not ?

In the past I have watered either from the top or from the bottom, and always waited until the soil was dry on the top before watering again. But if the plants receive continuous water via the wicks from a reservoir, do I need to give the watering a rest period of several days once I see the bottom is empty ? Or should I refill right away in order to have a continuous water supply in the reservoir ? Will this not be too much water and prevent the top from drying out ?