FMK Flow Monitoring Kit by Bulk Reef Supply unlocks a world of control for any Apex model. The kit includes a 1" FS-100 Flow Sensor, two 1/2" FS-50 Flow Sensors, a Fluid Monitoring Module (FMM), and various adapters. It's designed for monitoring flow rates, leak detection, water level detection, and powering accessories, making it essential for any aquarium setup.