Tank Controller Overview

The Open Acidification Tank Controller

Finished Device

The Open Acidification Tank Controller is a device to control temperature and pH in an experimental aquarium and is intended for ocean acidification research. However, the Tank Controller can be used by anyone who wants to precisely control temperature and/or pH in an aquarium. The Tank Controller costs approximately $150 to build and has many of the features that units costing many times more.

To control pH, the Tank Controller can connect to a glass pH electrode to detect the pH of the aquarium. The Tank Controller can lower tank pH by interfacing with a solenoid valve attached to a CO2 regulator to bubble CO2 into the aquarium.

Temperature is controlled by attaching a PT-100 temperature probe to the Tank Controller to sense temperature of the aquarium. Temperature can be raised or lowered by interfacing with a aquarium heater or chiller.




  • KiCad - KiCad files for PCB design for Open Acidification pH-stat unit
  • Housing - 3D models to print housing for pH-stat unit