Meters

GroStar EC Calibration Kit (2.77 EC, 8 oz. each)
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GroStar by Apera EC Calibration Kit (2.77 EC, 8 oz. each)   • 2.77 EC conductivity standard calibration solution • Used as a reference or checking solution to ensure you have adequately cleaned the EC/ppm probe • Calibration Solution should be stored in a cool place out of direct sun and heat. • Non-hazardous product • Please keep out of reach of children  • Made in USA
$14.99
Availability: 5 in stock
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GroStar GS1 pH Pen
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Lab grade instruments designed specifically for growers!   pH 7 & pH4 calibration solution (50ml bottle each) KCL storage solution (10ml bottle) Lanyard and user manual
$115.99
Availability: 10 in stock
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GroStar GS1-E replacement pH electrode
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GroStar GS1-E replacement pH electrode   • Replacement GS1 probe measures pH and temperature • Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance • Low-resistance lithium glass membrane • double junction structure uses blue gel electrolyte without the air bubble 
$50.99
Availability: 2 in stock
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GroStar GS2 Soil pH Pen
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GroStar GS2 Soil pH Pen Lab grade instruments designed specifically for growers!pH 7 & pH 4 solution (50ml bottles of each) • KCL soaking solution (10ml bottle) • Cleaning brush • Hole dibber • Lanyard and user manual
$256.99
Availability: 10 in stock
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GroStar GS2-E replacement Soil Spear pH electrode
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GroStar GS2-E replacement Soil Spear pH electrode • Spear pH Probe measures pH and temperature in nutrient solution, soil, coco coir, rockwool, and many other media types • Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance • Impact-resistant spear glass tip, 10 times stronger than conventional glass bulb • PTFE ring prevents a clogged junction caused by soil particles, significantly increases durability • Backed by Apera's Swiss LabSen proprietary sensor technology
$181.99
Availability: 2 in stock
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GroStar GS3 EC Pen
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GroStar GS3 EC/PPM/Temp Pen Lab grade instruments designed specifically for growers! Features: • Measures conductivity EC, PPM (500), PPM (700) and temperature • Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance • Titanium alloy sensor designed for high accuracy EC measurement • Easy-to-use design and fast calibration adjustment. • Large 3-color backlit screen gives you clear information • IP67 waterproof rating  • Replaceable probe • Powered by AAA batteries with auto off function • Automatic temperature compensation
$113.99
Availability: 10 in stock
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GroStar GS3-E replacement EC electrode
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GroStar GS3-E replacement EC electrode • Measures conductivity EC, PPM (500), PPM (700) and temperature • Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance • Titanium alloy sensor designed for high accuracy EC measurement
$53.99 $49.99
You save: $4.00
Availability: 2 in stock
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GroStar GS4 pH/EC/500ppm/700ppm/Temp (5-in-1) Combo Pen
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Lab grade instruments designed specifically for growers! Measures pH, conductivity (EC and 500ppm/700ppm) and temperature (5-in-1). Compatible with all GroStar replacement probes: pH, Soil pH, EC and PH/EC Combo. Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance. Easy-to-use design and fast calibration adjustment. Double junction replaceable probe, so you don’t have to discard the entire pen when the probe reaches its end of life.
$178.99
Availability: 10 in stock
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GroStar GS4-E replacement pH/EC combo electrode
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GroStar GS4-E replacement pH/EC combo electrode • Measures pH, conductivity (EC and PPM) and temperature • Combo probe built with lithium glass membrane and titanium alloy to ensure high accuracy and durability • Premium probe technologies and materials ensure high accuracy and durability with minimal maintenance • double junction structure uses blue gel electrolyte without the air bubble 
$79.99
Availability: 2 in stock
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HM Digital COM-80 EC/TDS/Temp Waterproof Hydro Tester
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The COM-80 is an economically priced, reliable EC/TDS meter that is ideal for testing applications such as hydroponics & gardening, pools & spas, aquariums & reef tanks, water ionizers, drinking water and more.
$42.95
Availability: 10 in stock
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HM Digital PH-200 Waterproof pH/Temperature Meter
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Measures pH and temperature Auto-ranging three point calibration with digital fine tuning Includes 4 pH buffer solution in a sponge embedded in a clear cap, so you can see if it's dried up Waterproof housing Simultaneous temperature display
$101.92
Availability: 10 in stock
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hf-HMDPHM80
The PH-80 is an economically priced, reliable pH meter that is ideal for testing applications such as hydroponics & gardening, pools & spas, aquariums & reef tanks, water ionizers, drinking water and more.
$46.50
Availability: 50 in stock
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