Hi, we are working on adding flow sensor support to the firmware and at the moment the plan is to support one flow meter connected to the rain sensor port. So the rain sensor port will have dual functions: you can either use it to connect a rain sensor or a flow sensor. At the moment we cannot support more than one flow sensor — but in most cases one flow sensor is probably sufficient, especially since in most cases the stations run in sequential mode. Robert on the forum has provided his implementation of flow sensor, and our code will be based on his as a starting point.