Neptune Systems is at it again! By adding even more to their ever growing line up of aquarium gear Neptune Systems is quickly becoming a one stop shop for all the equipment you need to keep a saltwater reef aquarium running successful and as hassle free as possible. Before we lose you please note that the new ATK or Automatic Top Off Kit can be used with or without the Apex controller as a stand alone unit!

Let's proceed!

With many options in the industry for replacing evaporated water Neptune Systems set out to create their very own unique Auto Top Off unit or as they like to call it, the ATK or Automatic Top Off Kit. So why create a new way to replace water when there are so many other units already available in the hobby? Neptune Systems tells us exactly why on the new ATK product page.

"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."

So what are the key benefits to owning the ATK? Neptune Systems outlines each of these as the following:
  • 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
Check out this video where Terence from Neptune Systems shows what the ATK is all about.

Auto topping off your evaporated water can be scary and stressful for those who are not comfortable automating this crucial step of owning an aquarium. If this is you then take heart because the ATK also boasts multiple layers of fail safes to prevent flooding and other disastrous effects of overfilling your aquarium. And let's face it. It sure beats lugging around heavy buckets! So what makes the ATK "safer" to use than many other ATO's in the hobby? Neptune Systems outline the following:

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.


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.

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


The premise for every auto top off system is inherently the same but many differ in how they go about achieving the same results which is replacing evaporated water. That's where the uniqueness of the ATK comes into play. What makes the ATK different? Check out the following straight from the product page!

1. Apex owners get even more value
If you already have an Apex of ANY kind, setting up the ATK is still super-simple. Just plug in all the components, attach it to your Apex via the AquaBus cable, and then run the set up task inside Apex Fusion. With the ATK connected to an Apex, you get the added benefit of having email/text/iOS alerts if there is an emergency and you can integrate its operation into other functions.

2. IQ-Fill (standalone mode only)
IQ-Fill is an intelligent and learning algorithm that, ongoing, monitors and records how much water your aquarium needs for each fill, and then calculates a maximum time your pump should run. By doing this, it dramatically reduces the chance that your pump would continue to add large volumes of water to the tank before you could realize it and fix the situation

3. Back-up mechanical float valve
While a float valve mechanism itself is certainly no high-tech solution, it is exactly what you want to have in place should all this high-tech gear decide to fail. The float valve on the ATK will never see any action unless for some reason the electronics continued to add water to the tank despite the optical sensors being submerged and the IQ-Fill algorithm limiting run times. For those small systems (usually small all-in-one aquariums) where the float valve will not fit, you can remove the float valve from the bracket and you still will have two levels of safety backup.

4. PMUP – the most powerful pump provided with any ATO!
The PMUP is a 24V utility pump that is perfect for moving water from your RODI reservoir to the aquarium. This pump has a vertical design that easily drops into most water jugs or ATO reservoirs. The best part about the PMUP is that it has the the power to deliver water to your tank even from remotely located water reservoirs. Most other pumps that come with an ATO will barely pump six feet, the PMUP though has the ability to pump over 14’ vertically so it can even pump water up from a lower-floor or basement water storage location!

We really like the idea of the new ATK and all the redundant safety features it includes as well as the functionality that it has. So what about price and availability you may ask? In the USA the ATK retails for $199.95 and is currently available at all major Neptune Systems dealers both online as well as local marine aquarium stores.