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Neptune Systems Automatic Top-off Kit

Neptune Systems Automatic Top-off Kit

Regular price $339.99
Regular price Sale price $339.99
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Neptune Systems Automatic Top-off Kit - ATK V2

The ATK (Automatic Top-off Kit) is a simple, standalone, and complete solution for replacing water lost to evaporation.

The new aquarium hobbyist has many challenges, but none is more annoying than the chore of adding water, every day, to make up for that lost to evaporation (a.k.a. topping off/up). This alone usually makes the automatic top-off (ATO) device the first piece of automation equipment purchased.

The ironic flip side of this decision is that a faulty ATO device is one of the leading reasons for catastrophic aquarium failure, or even worse, flooding of the house or business.

Not all ATO devices are created equal. Sadly, many ATO on the market are made with cheap components, have very little protection against these catastrophes, and are just a nightmare to assemble and install correctly.

An ATO does not have to be both a blessing and a curse!

We designed our ATK – Automatic Top-Off Kit to not only be super-simple to install and use, but it is unique in the market as an ATO device with three layers of redundant monitoring and water-level control. The ATK does the work for you, while at the same time protecting your tank and your home.


Plug and play ready. No mounts to assemble. No bare wires to attach.
3 Levels of Safety Protection!
Two optical water-level sensors (one for water level and one for emergency back up)
IQ-Fill water run-time intelligence – learns how much water you use at each top-off
Mechanical float valve prevents water overrun if electronics should ever fail
Does NOT rely on ANY fault-prone mechanical float switches, temperature sensors, or capacitive sensors!
Works Standalone (NO APEX NECESSARY!)
Advanced features are unlocked when connected to an Apex (i.e. remote failure notification via text, email, or iOS alert)
Includes PMUP, a powerful 24VDC pump that can push water vertically up to 14’
Audible failure alarm
Additional features with optional accessories

1. Backup Optical Sensor
Should the main water level sensor fail, this second optical sensor is the backup. If water continues past the primary sensor, and then covers this one, the pump will be shut off and an alarm will sound.

2. IQ-Fill – Water run-time intelligence
If both the primary water sensor AND the backup optical sensor fail, the algorithm used in the ATK will not add more than double the learned water amount. It will shut itself off and sound an alarm.

3. Physical float valve – the final backstop
If for some reason all the electronic failsafes do not work, and water is continuing to be sent to the aquarium, the mechanical float valve is the safety device that will stop the water and prevent death to your aquarium and water on your floor.


FMM – Fluid Monitoring Module (runs standalone)
Pre-assembled water level mechanism with:
Magnetic acrylic mount (works up to 1/4″ glass/acrylic)
Two (2) optical water level sensors
Float valve
90 degree tubing fitting
New and imporved PMUP ATO Pump
24V 36W power supply
4m of orange RO tubing
3/8″ -> 1/4″ push-fit adapter fitting
1/4″ -> 1/4″ push-fit siphon break
Set-screw for non-float-valve applications
Improved Optical sensors
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