AOS 5.10_8A22 has been released. This AOS version contains support for the recently announced new A3 Apex models and the new Fluid Monitoring Module (FMM) sensors, which will soon be available for purchase. This AOS may be installed on any Apex model made since 2016 - the Apex (now known as the A2 Apex and the Apex EL (now known as the A2 Apex EL), as well as the newest A3 series.

Information about the new A3 Apex family of controllers may be found on A3 Apex Series page of the Neptune Systems website
Information about these new sensors may be found on the FMM Accessories page of the Neptune Systems website.

This AOS release adds several new features and capabilities:

Support for six new Fluid Monitoring Module sensor accessories

  • Liquid Level Sensor – LLS-4 (4”)
  • Liquid Level Sensor – LLS-15 (15”)
  • Liquid Level Sensor – LLS-23 (23”)
  • Liquid Level Sensor – LLS-35 (35”)
  • Optical Multi-Surface Leak Sensor- LD-3
  • Magnetic Optical Sensor - MOS


Updated APEX Local user interface

  • Streamlined and enhanced automatic and manual calibration routines for all probes (Temperature, Salt/Conductivity, pH, DO, and ORP)
  • New advanced program editor with improved keyword and name matching, as well as program statements templates which allow you to pick a template which will enter a complete and syntactically correct statement for you which can then be customized.


SKY software

  • The new SKY firmware version is 16; this version contains a minor enhancement for SKYs which might later be used in standalone operation; you will not see any difference with Apex-connected SKYs.


FMM software – this AOS update includes new FMM software. The new FMM software version is 23; this update for the Fluid Monitoring Module has the following enhancements:

  • Adds support for the new sensors listed above
  • New audible alarm - This update enables the use of the audible alarm buzzer in the FMM through a new output. When your FMM is updated to version 23 firmware, a new output will be created automatically . It will be named Alarm_#_2, with # being the Aquabus address of the FMM. This new output, when ON, will energize the audible alarm buzzer built into the FMM, which was previously only used when the FMM was part of an ATK operating in standalone mode. You may rename this output as desired and you can program this output using any desired alarm conditions.
  • Auto-detect changes – This update changes the FMM port Auto-Detect behavior. Previously, the Auto-Detect function could be kept enabled, or be optionally disabled on a per-port basis. Now, Autodetect will be disabled automatically for a FMM port as soon as you make any change to that FMM port’s configuration. Once Autodetect is disabled for a given port, it cannot be re-enabled through the APEX Local or APEX Fusion user interfaces. For those of you who used to use an Apex Classic with your ATK, FMK, or LDK, it now works just like it does for a FMM connected to an Apex Classic model.


After updating to this newest AOS, wait 5-10 minutes, then update your FMM(s) and/or SKYs:

1. Go to the Modules List in APEX Fusion or APEX Local
2. Click or tap on a FMM or SKY module
3. In the Configuration area, select the Update Software option, then click or tap the orange Send button.
4. Wait for the module update to complete
5. Repeat Steps 2-4 for any additional FMMs any SKYs



After updating your FMM to v23 software, please disconnect Aquabus cables and the 24VDC power supply (if one is in use) from the FMM for about 5 seconds, then reconnect Aquabus and power. Repeat for each additional FMM you have.

NOTE: This AOS version will become available to A2-series Apexes in phases over the next two weeks. You might not see it as being available to your Apex right away. Just periodically check the Network page in APEX Fusion or APEX Local to see it it is available to your Apex.


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