Not even once per week and water it from the roots. You want to put it into a dish and use the dish as the water source so the water doesn't hit the leaves.
Water the plant after the top of the soil become dry. Watering will depends on light and heat. We can also use Shulz fertilizer if the plants are flowering properly. Make sure to fertilize on every watering. In the winter have less watering and fertilizer.
The african iolet plants are very delicate and since they need very less water. These plants should be kept in the shade, and the water should be sprayed if possible.