1/2″ Flow Sensor by Neptune Systems

1/2" Flow Sensor by Neptune Systems – Aquarium Flow Sensor for Apex control

The 1/2" Flow Sensor by Neptune Systems delivers real-time readings to Apex for reliable tuning and alerts. Built by Neptune Systems, it fits naturally within Automate and Monitor workflows as a compact Neptune Systems Flow Sensor.

1/2" Flow Sensor by Neptune Systems – place within Aquarium Controllers and Flood Control and Leak Sensors

Use this Flow Sensor Neptune Systems in Aquarium Controllers layouts. Then pair it with Flood Control and Leak Sensors to spot issues before they escalate.

Why this Aquarium Flow Sensor earns a spot

• Measures 30–250 GPH on 1/2" slip PVC

• Connects to the FMM and reports directly to Apex

• Includes unions that adapt BSPP threads to 1/2" slip

• Confirms return output after maintenance or valve tweaks

• Helps reveal clogs, air entrainment, and output drift

Everyday uses that make a difference

• Validate reactor and UV manifold branches

• Track nano return lines with precision

• Log baseline flow for easier troubleshooting

• Create Apex alerts for low-flow events

Installation at a glance

1. Dry-fit the unions on your 1/2" slip PVC.

2. Solvent-weld, then align the arrow with the flow.

3. Plug the sensor into an FMM port.

4. Calibrate in Apex and set alert thresholds.

Tips for clean, stable readings

• Keep 6–10 inches of straight pipe before the sensor.

• Purge microbubbles at startup.

• Recheck unions after the first warm cycle.

• Secure cables away from heat and salt spray.

Specifications for the 1/2" Flow Sensor by Neptune Systems

• Pipe size: 1/2" slip PVC (via included unions)

• Flow range: 30–250 GPH

• Sensor thread: BSPP (adapted by unions)

• Interface: FMM input to Apex

• Orientation: Inline, arrow matching flow direction

What’s Included

• 1× 1/2" Flow Sensor

• 2× BSPP-to-1/2" Slip Unions

FAQ about the 1/2" Flow Sensor by Neptune Systems

Do I need an Apex FMM?
Yes. The sensor reports through an FMM port to Apex.

Will it restrict my 1/2" line?
Restriction is minimal when installed on full 1/2" PVC.

Can I mount it horizontally?
Yes. Keep the body level and follow the flow arrow.

How much straight pipe should I leave?
Aim for 6–10 inches before the sensor for stability.

Can I use flexible tubing?
Transition to hard 1/2" PVC, install the sensor, then return to hose if needed.

Why do early readings bounce?
Air and microbubbles cause swings. Bleed air and stabilize valves after priming.

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