Neptune Systems ATK V2 Auto Top Off Kit

The ATK (Auto Top-Off Kit) by Neptune Systems is a robust, plug-and-play ATO system designed to top off evaporated water automatically — without requiring an Apex Controller. With three levels of redundancy, intelligent water control, and a powerful 24V DC PMUP pump, the ATK provides a reliable and safe way to automate one of reefing’s most tedious daily tasks.

While the ATK functions completely as a standalone unit, it can also be connected to a Neptune Apex Controller for enhanced features, remote notifications, and system-wide integration.

Key Features

• Plug & Play ATO — No Apex required

• Dual optical sensors (no moving parts)

• IQ-Fill intelligent water run-time control

• Mechanical float valve for added safety

• Audible alarms on failure

• Includes PMUPv2 Utility Pump (24V DC)

• Expandable via FMM ports

• Advanced features unlocked when paired with Apex

Designed for Convenience

Topping off evaporated water is one of the most repetitive and essential maintenance tasks in reef keeping. The ATK simplifies this with automated, precise water replenishment — keeping salinity stable and water levels consistent, whether you’re home or away.

Ideal for:

• Daily top-offs from your RO reservoir

• Travelling without tank-sitting arrangements

• Reducing salinity swings in small- to medium-sized systems

Three Levels of Redundant Safety

1. Primary Optical Sensor
   Controls normal water replenishment cycles.

2. Backup Optical Sensor
   Shuts off the pump and triggers an alarm if the primary sensor fails.

3. Mechanical Float Valve
   A final failsafe — halts water flow even if both electronic sensors fail.

4. IQ-Fill Technology (Standalone Mode)
   Learns how much water is typically needed and won’t exceed double that amount during any given top-off session. If exceeded, the pump stops and an alarm sounds.

PMUPv2 – Powerful Utility Pump

The included PMUP v2 is a compact, submersible pump rated for:

• Up to 4.3 metres (14 feet) of vertical head height

• Ideal for most jugs, barrels, or remote water containers

• Removable screen for easy cleaning and debris prevention

• Runs on 24V DC for improved energy efficiency and safety

Extra Functionality for Apex Users

While fully operational on its own, the ATK gains additional features when connected to a Neptune Apex system:

• Email and mobile alerts via Apex Fusion

• Custom top-off programming

• Integration with other sensors (leak detection, flow monitoring, etc.)

• Use additional FMM ports for extra sensors or accessories
  (2 out of 4 ports are used by the ATK)

Setup with Apex is simple — just plug in the AquaBus cable and follow the ATK setup task in the Fusion dashboard.

Specifications

• Sensors: 2x Optical Water Level Sensors

• Backup: 1x Mechanical Float Valve

• Pump: PMUP v2 (24V DC)

• Tubing: 4 m of 6 mm (¼”) RO Tubing

• Max Pump Head: 4.3 m

• Power Supply: 24V 36W

• Expandable Ports: 4 (FMM Module), with 2 used by ATK sensors

• Operation Mode: Standalone or Apex-controlled

What’s Included

• 1x FMM Fluid Monitoring Module

• 2x Optical Water Level Sensors

• 1x Mechanical Float Valve

• 1x 90° Tube Fitting

• 1x PMUP v2 Utility Pump

• 4 m Orange RO Tubing

• 1x ⅜” to ¼” Push-Connect Adapter

• 1x ¼” Push-Connect Siphon Break

• 1x Set Screw (for non-float valve setups)

• 1x 24V 36W Power Supply

  Note: Advanced features require an Apex A2 or A3 Series Controller. ATK works as a complete standalone unit out of the box.