DIY Neptune Apex Display Module + Dosing Calculator


Supporting Member
Needed a release from a rather stressful couple of weeks at work, so decided to treat myself to a DIY project.

After upgrading my AQI monitor (see details here) hardware to a bigger screen/microcontroller, I had to find a use for the old module.

Enter: The Neptune Apex, and my need for manual dosing of Calcium + Magnesium supplements.

I decided to solve my #firstworldproblem of opening JDieck's calculator on my phone, punching the numbers in, and calculating Calcium/Magnesium supplement values.

Screenshot 2022-01-13 183013.jpg

Luckily, Neptune Systems provides a wonderful API to access data from the Apex and its peripherals.
For the sake of completeness, some of the URLs are:
  • http://<<apexIP>>/cgi-bin/status.xml
  • http://<<apexIP>>/cgi-bin/program.xml
  • http://<<apexIP>>/cgi-bin/outlog.xml
  • http://<<apexIP>>/cgi-bin/datalog.xml
  • http://<<apexIP>>/cgi-bin/status.json
I wrote some code to pull in data from the Apex over WiFi using this API.
This data is used to calculate the dosing quantities required for my specific supplements/tank volume, and the microcontroller then displays everything neatly on a small LCD screen.
The calculations were based on JDeick's trusty Reef Chemistry Calculator.

Now the process is as simple as looking at the module, dosing the displayed quantities, and tapping the screen to reset the notification.


This ain't no badass @phatduckk 's ReefTiles, but a simple solution to my #firstworldproblem.

If y'all have any thoughts or suggestions for improvement, I'd love to hear them!
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