Bluelab pH Pens, EC Meters & Nutrient Controllers
Bluelab is the commercial benchmark brand for hydroponic water quality measurement -- their instruments are found in more professional growing operations than any other pH and EC meter brand. The company's focus is narrow and consistent: build the most reliable, accurate, and grower-practical measurement instruments available for pH, electrical conductivity, and temperature management in hydroponic nutrient programs. Every Bluelab product is designed specifically for the demanding conditions of commercial hydroponic growing -- continuous use, nutrient solution exposure, and the accuracy requirements of EC-based precision feeding programs.
Bluelab pH Pen & Combo Pen
The Bluelab pH Pen is one of the most widely used professional pH meters in commercial hydroponics -- a compact digital pen with automatic temperature compensation (ATC), waterproof construction, and a probe design calibrated for nutrient solution environments that holds accurate readings between the monthly calibration intervals that commercial use requires. The Bluelab Combo Pen adds EC (electrical conductivity) and temperature measurement to the pH pen in a single device, eliminating the need to carry two separate meters for complete nutrient solution management. Both include storage caps compatible with Bluelab's electrode storage solution for proper probe care between uses. See our updated best pH testers guide for a full comparison across brands and formats.
Bluelab Truncheon EC Meter
The Bluelab Truncheon is the most widely used EC meter in commercial hydroponic operations -- a no-calibration-required design that maintains accuracy through an electronic reference system rather than a calibration buffer. The Truncheon displays EC (mS/cm), PPM-500 (Hanna scale), and PPM-700 (Bluelab scale) simultaneously, eliminating confusion about which PPM scale is being used. Its durable, fully waterproof construction and no-calibration design make it the most practical EC meter for commercial operations where consistent daily use and minimal maintenance overhead are priorities. For growers who want automated continuous monitoring rather than manual spot-checking, the Bluelab Connect system provides real-time pH and EC logging to a central dashboard. Expert support available.
Bluelab FAQ
Why is the Bluelab Truncheon so popular in commercial hydroponics?
The Truncheon's primary advantage is its no-calibration-required design -- it uses an electronic reference system that maintains accuracy without calibration buffer solutions or periodic recalibration procedures. In commercial operations where pH and EC meters are used multiple times daily by multiple operators, the calibration-free design eliminates a key source of measurement error (improperly performed or missed calibrations) and reduces maintenance overhead significantly. Its simultaneous display of EC, PPM-500, and PPM-700 also eliminates the PPM scale confusion that causes feeding program errors when operators switch between different meter brands. Its durability and fully waterproof construction further suit it to the continuous use demands of commercial hydroponic operations.
How often should I calibrate a Bluelab pH Pen?
Bluelab recommends calibrating their pH pens monthly under normal use conditions. Monthly calibration with fresh buffer solutions (pH 7.0 and pH 4.0 two-point calibration) maintains accuracy within the 0.1 pH tolerance that professional hydroponic programs require. Between calibrations, verify the pen is reading correctly by checking against a fresh reference buffer solution -- if it reads outside 0.1 pH of the buffer value, recalibrate immediately. Store the probe in Bluelab's KCl electrode storage solution between uses to maintain the probe's reference electrolyte and extend probe lifespan. See our pH pen calibration guide for step-by-step calibration procedures.
What is the difference between the Bluelab Combo Pen and separate pH and EC pens?
The Bluelab Combo Pen measures pH, EC (mS/cm), and temperature from a single device with a single probe insertion -- convenient for growers who want one tool for complete nutrient solution testing. Separate pH and EC pens provide dedicated single-function accuracy, independent calibration and replacement, and in the case of the EC Truncheon, a no-calibration design that is not available in the Combo. For operations where a single operator checks both parameters routinely, the Combo is the most convenient option. For commercial operations where pH and EC are checked independently by different staff, or where the Truncheon's no-calibration design is valued for EC accuracy, separate dedicated instruments may be more appropriate.
