The Open acidification Tank Controller: An open-source device for the control of pH and temperature in ocean...

Ocean acidification research has faced challenges due to the high cost of laboratory tools for controlled experiments. It was already known that rising atmospheric CO₂ levels influence seawater chemistry. However, no prior work had resolved how to reduce equipment costs without sacrificing precision. Researchers have shown that pH and temperature control are essential for simulating realistic ocean conditions. Yet, no affordable alternatives existed for maintaining these parameters in aquaria. That uncertainty drove the development of low-cost devices for marine research. This gap motivated the design of a system that could match commercial standards at a fraction of the cost. No prior work had resolved the feasibility of using open-source hardware for pH and temperature regulation. This gap motivated the creation of a device that could be widely adopted in marine research settings.

The aim of the study was to develop an affordable device for ocean acidification experiments. The specific problem addressed was the high cost of commercial pH and temperature control systems. The motivation stemmed from the need to expand access to controlled marine research tools. No prior work had resolved how to integrate web-based monitoring with low-cost hardware. The goal was to create a system that could maintain precise pH and temperature setpoints. The study sought to demonstrate that open-source components could achieve research-grade performance. The purpose was to enable broader adoption of ocean acidification experiments in academic settings. This approach aimed to reduce financial barriers without compromising scientific accuracy.

The device uses an Arduino Mega 2560 as the central controller. It is housed in a 3D printed enclosure for durability and accessibility. A BNC glass pH probe measures pH levels with high accuracy. A three-wire PT100 sensor tracks temperature changes in real time. The system allows for pH and temperature adjustments based on user-defined parameters. Web-based reporting enables remote monitoring of aquarium conditions. Data is stored on a micro-SD card for later analysis. The device supports multiple control modes including sine-wave fluctuations.

The device successfully maintained pH and temperature within specified ranges. It achieved performance comparable to commercial systems at a lower cost. The system could hold setpoints with minimal deviation over time. It supported ramping between values and sine-wave fluctuations as programmed. Data storage on micro-SD cards ensured continuous monitoring. Web-based reporting allowed real-time access to experimental conditions. The device was assembled for less than $250 per aquarium setup. These results suggest the system is suitable for marine research applications.

The authors propose that the Open Acidification Tank Controller is a viable alternative to commercial devices. It may reduce costs while maintaining necessary precision for ocean acidification studies. The system's design allows for customization and adaptation to different research needs. The researchers suggest that this device could expand access to controlled marine experiments. The device's affordability may encourage broader adoption in academic and research settings. The system's performance suggests it could support a range of experimental designs. The authors propose that this device may help address the financial barriers in marine research. These findings suggest the device could be a valuable tool for ocean acidification investigations.