Usually used with aquarium accessories like RODI inputs, calcium reactor feed lines etc., this flow sensor can be placed in line with the flow on 1/4" tubing, connected to the Fluid Monitoring Module, and communicate to your Apex the flow rate of water through that pipe. The flow sensor itself uses push-fit connectors to make connecting to your system as simple as possible.  The FS-25 will work with flow rates from 3-12 gph.

The 1/4" Flow Sensor is a product in the Neptune Apex AquaController System line and is compatible with all APEX systems (Apex Jr, Apex Classic, Apex Lite, Apex). The Neptune Apex System is probably the most technologically progressive comprehensive aquarium system on the market. Featuring full wireless compatibility, customization, and control, the Neptune Apex System is unrivaled by its competitors. This system is the future of the home aquarium. You can set up the system to send you email alerts on any number of factors, alarms, or even phone notifications to monitor tank conditions. The system is fully customizable and will receive regular software and firmware updates to ensure continued efficiency and to keep the system as up-to-date on current trends as possible. All products are interchangeable and customizable and will fit into other products seamlessly with no programming required.