Cuboid Aquatics Wifi Digital pH ControllerThe Cuboid Aquatics Wifi Digital pH Controller allows you to monitor pH, TDS and Temperature thru your smartphone. You can set alarms and even receive alerts with a subscription service. You can also use the controller to turn a CO2 solenoid on and off to maintain the pH level you set 24 7. Keep the stable pH level your fish and plants require without daily fluctuations. No need for a timer.