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Neptune Systems

A3 Apex Jr Aquarium Monitor (A3JRSYS) - Neptune Systems

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A3 Apex Jr Aquarium Monitor (A3JRSYS) - Neptune Systems
A3 Apex Jr Aquarium Monitor (A3JRSYS) - Neptune Systems
A3 Apex Jr Aquarium Monitor (A3JRSYS) - Neptune Systems
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In Stock - Get it tomorrow Fri, Jun. 14th with paid overnight shipping, order by 1 pm today.

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A3 Apex Jr Aquarium Monitor (A3JRSYS) - Neptune Systems
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The A3 Jr is a Monitoring Only solution.  You can not turn anything on or off with it straight out of the box.  It becomes a full controller however as soon as you add a Powerbar.  To make it a full controller just buy an Energy Bar 832 or EB4 and connect it via aqua bus, then you will have a full monitoring & controllable system.

The A3 Jr will be a new, "monitoring-only," system that offers the same monitoring the A3 Apex offers without the control of the EB832.  The A3 Apex Jr. is the first monitoring only solution that monitors exactly what you need; and, when ready, opens the door to control for all aquarist.

The most successful aquariums are those where the owner has the most understanding of what is going in their little world-in-a-glass-box.  However, the real key to enjoying this hobby is to do that without making it a full time job!

Owning the Apex is the best way to get you back to focusing on the things you love like your fish and coral, and less about temperature issues, pH levels, light timers, dosing tanks, vacation plans, etc.

The most important aspect of having an Apex though is the disaster prevention it provides. The Apex will notify you when things go bad, giving you time to take action and prevent an aquarium catastrophe.

Of course you also unlock the door to more advanced things such as LED dimming, variable pump control, auto top-off, calcium reactor control, ozone control, auto dosing of elements, auto-feeding your fish, and much more!

Neptune Systems A3 Apex Jr System -- Get the essential monitoring you need now, expand into control later

  • A3 Apex Jr base unit
    • 2 FMM Ports
    • 2 Aquabus Ports
    • 1 pH/ORP* probe port
    • 1 Temperature probe port
    • WiFi compatible only (no Ethernet port)
    • New built-in audible alarm
    • Expandable
  • Track temperature and pH with included lab-grade, double-junction probes
  • Monitor water level with new MOS Magnetic Optical Sensor
  • Stay on top of leaks with LD-2 Leak Detection Floor Sensor
  • Set reminders, log testing and dosing information, and access your tank from anywhere
  • Affordable entry into Apex ecosystem with ability to add-on/expand as you see fit

*ORP probe sold separately


In addition to all the incredibly cool things an Apex does, first and foremost it protects your tank from all sorts of very common catastrophes like overheating due to faulty tank heaters or HVAC issues, leakages and overflows, out of range parameters, etc. And, once issues are detected, the Apex can take corrective action to reduce the likelihood of serious damage and then notifies you so you can take it from there.

Apex systems have already saved many aquarium owners thousands of dollars in livestock, equipment, flooring, etc.  Leaving home for 2 hours or 2 weeks will no longer involve the anxiety of wondering what you will come home to. This reason alone is enough to justify purchasing an Apex.


  • Prevents catastrophes by monitoring key parameters in your aquarium, takes corrective actions for you, and alerts you via your smart phone when things go off track.
  • Monitors your equipment – ensuring it is operating correctly at all times – and lets you know when it’s not.
  • Tracks your manual test results, maintenance, livestock purchases, and tank observations and helps you correlate issues in your aquarium to the things that are happening inside.
  • Manages the full operation of equipment (lights, pumps, filters, ATO, etc.) on your tank with simple setup wizards and an easy to use app.
  • Takes the place of many costly and cumbersome discrete components such as light timers, heater controllers, pump controllers, etc.
  • Gives you the peace of mind to know how your aquarium is doing, instantly, from anywhere in the world.

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