Electronic pH Testers

Hand-Held

Simply Hydroponics and Organics stocks several makes of hand-held pH meters. These meters are often called "pens". These pens make quick work of pH measurement, just turn the meter on and dip the tip in the nutrient tank, the pH value is displayed on the LCD readout. 

The Oakton pH 1 and pH 2 are identical except the pH 2 has automatic temperature compensation and the pH 1 doesn't. Oakton pens are waterproof and come with a replaceable electrode. 

Shindengen ISFET pH Meters (KS501) are state-of-the-art pH pens and work with a totally different method of measurement. This pens use a solid state Ion Sensitive Field Effect Transistor   (ISFET) instead of the fragile glass electrodes used by traditional pH pens. The Shindengen pH pens have replaceable tips that change from opaque to clear when it needs to be changed. The manufacturer claims that this solid state pH pen is more reliable and will last longer than traditional pH pens.