GAIN EXPRESS
Digital Combo pH & Temperature Meter, Aquarium Thermometer pH Monitor with Automatic Calibration Function for Fish Tank Hydroponics Aquaculture Laboratory
VACSAX
Water Quality Tester, Rechargeable Digital pH Meter, 5-in-1 pH TDS EC Salinity Temp, with Simultaneous Data Display, for Hydroponics, Drinking Water, Aquarium, Spas, Lab
Bluelab
Bluelab PROBPH pH Probe for Water, Replacement Electrode for Meter, Monitor, and Controller with Easy Calibration, Tool for Hydroponic System and Indoor Plant Grow
Bluelab
bluelab pH Pen-Digital pH Tester - Reliable & Accurate for High Yield Crops - Hand-Held Meter - Measures pH & Temperature in Solutions and Soil Solutions - Optimize Plant Health & Performance,White