pH & Temperature Water Pen - Ionix for Testing Water Quality in Hydroponic SystemspH & Temperature Water Pen Ionix for Testing Water Quality in Hydroponic Systems Ionix pH Temperature Pen With Carry Case The Ionix pH Temperature Pen is a versatile and durable tool for measuring pH and temperature in water. The large display screen allows for easy reading of the measurements even in low light conditions. The waterproof and dustproof housing ensures that the pen can withstand harsh environments making it ideal for use in a variety of