I’m using this sensor on a top-up system for an aquarium of mine. Because the water level drops slowly due to evaporation, I don’t have to worry about water droplets disrupting the signal, which another reviewer has stated can happen. The valuable part of the optical switch for me is that it’s impervious to disruption by snails. The snails can jam up magnetic float switches and cause them to stick in the fill position which can be disastrous. The sensor is indeed very sensitive, so waves and ripples in the water can disrupt it easily. I used a Resistor-Capacitor network to groom the signal for a Schmitt trigger to compensate for this. Overall, I love this sensor!