Neptune Systems PM1 pH/ORP Temp Probe Module

The PM1 Module is a compact, plug-and-play expansion device for any Neptune Apex system, providing an additional pH or ORP probe port, a temperature probe port, and an I/O port for connection to external switches via the Breakout Box.

Ideal for multi-tank setups, calcium reactors, or advanced automation needs, the PM1 allows aquarists to monitor and respond to more environmental variables within the Apex Fusion ecosystem.

Key Features

• Compatible with all Apex Controllers (A2 and A3 Series)

• Use the probe port for pH or ORP (not both simultaneously)

• Includes temperature probe port

• I/O port allows connection to the Breakout Box (sold separately)

• 2x AquaBus ports for easy daisy-chaining with other modules

• Plug-and-play setup via Apex Fusion

pH / ORP Monitoring

The main probe port on the PM1 can be used for either:

• A pH probe, to monitor a second tank or equipment like a calcium reactor

• An ORP probe, for ozone system control or general water quality tracking

Use cases include:

• Monitoring pH inside a calcium reactor to automate CO₂ flow

• Adding ORP monitoring to automate an ozone generator

• Running multiple tanks from one Apex controller with separate pH probes

Temperature Monitoring

A dedicated temperature probe port allows:

• Tracking of a second aquarium

• Monitoring ambient temperature in your cabinet or room

• Redundant temperature sensing for safety or environmental profiling

I/O Port for External Switches

The integrated I/O port allows connection to the Neptune Breakout Box (sold separately), giving you the ability to add:

• Float switches (e.g. for ATO or sump monitoring)

• Push buttons (e.g. to activate feed modes)

• Magnetic reed switches (e.g. for cabinet door alerts)

Up to six switches can be connected through the Breakout Box to trigger custom automation routines in Apex Fusion.

Specifications

• Probe Ports:

  • 1x pH or ORP (selectable)

  • 1x Temperature

• Expansion Ports:

  • 1x I/O port

  • 2x AquaBus ports

• Connectivity: Apex Controller (via AquaBus)

What’s Included

• 1x PM1 Module

• 1x 0.9 m (3 ft) AquaBus Cable

  Note: Probes, temperature sensors, and the Breakout Box are sold separately. Requires a Neptune Apex Controller.