Testing and Monitoring - pH, EC/TDS, PPM

Hippy guy Hippy guy

Whether using soil or hydroponics for your gardening, the proper balance of your growing environment can be the life or death of your plants. This area helps with the proper maintenance of:

pH: (chemistry) p(otential of) H(ydrogen)
TDS: total dissolved solids
PPM: parts per million
EC: electrical connectivity

Look through our selection of meter maintenance solutions. Find pH adjusters here.

Growco is a trained and certified Bluelab retail and warranty outlet.

We are HAZMAT approved to safely ship all of your PH control needs. We take great care in insuring that your packages will get to you in perfect condition, without leaking or being damaged in any way.

View the price list

Sort by manufacturer: Advanced Nutrients, Bluelab, Botanicare, Earth Juice, Espoma, Future Harvest, General Hydroponics, Generic, Hanna Instruments, Micro Essential Laboratory, Milwaukee, Oakton, Oregons Only Organics, Rapitest, SaferGro, Sunleaves, Technaflora

1382 ppm (EC/TDS) calibration solution - 230 ml

Calibration Solution allows you to calibrate your meter in moments.
$9.95

1413 ppm (EC/TDS) calibration solution - 230 ml

Calibration Solution allows you to calibrate your meter in moments.
$12.95

1500 ppm (EC/TDS) calibration solution - 230 ml

Calibration Solution allows you to calibrate your meter in moments.
$8.50

Advanced Nutrients pH DOWN

Advanced Nutrients pH balancing products are pure concentrates and have not been diluted.
$16.56 - $46.93

Advanced Nutrients pH UP

Advanced Nutrients pH balancing products are pure concentrates and have not been diluted.
$16.56 - $46.93

Bluelab Carry Case

The Bluelab Carry Case provides a custom fit so you can use and read your Bluelab Meter right from the carrying case. Simply zip it closed and your meter is protected during storage or transport.
$19.95

Bluelab Combo Meter

The Bluelab Combo Meter tests conductivity (nutrient), pH levels, and temperature, all in one convenient lightweight unit.
$249.95

Bluelab Conductivity Cleaning Kit

The level of conductivity is directly proportional to the amount of salts dissolved in water. The conductivity of your nutrient solution is a measurement of its strength, indicated by the actual amount of salts dissolved.
$19.95

Bluelab EC Solution - 250 ml

Bluelab 2.77EC Solution is used as a reference or checking solution to ensure the cleanliness and proper functionality of EC/CF probes.
$6.79

Bluelab Grower's Toolbox - Limited Edition

​The Bluelab Grower's Toolkit includes everything a hydroponics gardener could possibly need for comprehensive water quality testing.
$169.95

Bluelab Guardian Monitor

The Bluelab Guardian Monitor measures all three critical parameters to successful plant growth - pH, conductivity and temperature.
$299.95

Bluelab pH 4 Solution

Use Bluelab pH 4 Solution allows you to get the most accurate readings possible from your Bluelab products by ensuring they are clean and calibrated correctly.
$1.69 - $6.99

Bluelab pH 7 Solution

Bluelab pH 7 Solution makes sure all of your pH meters, monitors, and controllers and cleaned, calibrated, and ready to give you accurate readings.
$1.69 - $6.99

Bluelab pH Meter

The Bluelab pH Meter is used to accurately measure the pH value of nutrient solution.
$179.95

Bluelab pH Pen - ON SALE

The Bluelab pH Pen has been specially developed as an affordable, effective tool for hobby or small scale growers.
$84.95

Bluelab pH Probe

The Bluelab pH Probe is used to measure the pH of a solution.
$59.95

Bluelab pH Probe Clean Calibration Kit

Experienced growers suggest a pH level between 5.5 and 6.5 for most hydroponically grown plants. A dirty pH probe can skew the readings of your pH meter, resulting in a harmful growing environment.
$25.50

Bluelab pH Probe KCl Storage Solution - 100 ml

?Maximize the life and response time of Bluelab pH pens and pH probes with this KCI Storage Solution.
$9.95

Bluelab PPM Pen - ON SALE

The Bluelab ppm Pen measures conductivity and temperature to ensure your plants are receiving the proper amounts of nutrients.
$69.95

Bluelab Probe Care Kit - Conductivity

The Bluelab Probe Care Kit allows you to ensure your probe is clean and contaminate free for the most accurate readings possible.
$9.95

Bluelab Soil pH Meter

The Bluelab Soil pH Meter is a reliable pH meter that provides accurate readings of soil or hydroponics growing media.
$219.95

Bluelab Soil pH Pen

The Bluelab Soil pH Pen provides both pH and temperature readings of soil and grow media, an effective tool for hobby or small scale gardeners.
$149.95

Bluelab Soil pH Probe

The Bluelab Soil pH Probe serves as original equipment replacement for the Bluelab Soil pH Meter, but can also be attached to the Bluelab Combo Meter.
$94.50

Bluelab Truncheon - CF, PPM and EC meter

The Bluelab Truncheon Meter is the best selling hydroponics CF / EC Meter in the world. The Truncheon meter measures EC, CF and PPM scales.
$119.95

Botanicare pH Adjusters

Highly concentrated pH adjusters that help hold the pH in your reservoir stable for a long period of time.
$10.25 - $23.95

Earth Juice Double Down

Earth Juice Double Up and Double Down are potent pH adjusters that can be used in hydroponics systems or with soil based gardens.
$9.50 - $21.95

Earth Juice Double Down AND Up - 1 quart each

Earth Juice Double Up and Double Down are potent pH adjusters that can be used in hydroponics systems or with soil based gardens.
$17.95

Earth Juice Double Up - 1 quart

Earth Juice Double Up and Double Down are potent pH adjusters that can be used in hydroponics systems or with soil based gardens.
$9.50

Earth Juice Natural pH DOWN

Proper pH levels are crucial for healthy plant growth. A pH that is too high or too low can reduce the availability of some nutrients causing plant stress.
$14.31 - $49.95

Earth Juice Natural pH UP - 2 lb

Proper pH levels are crucial for healthy plant growth. A pH that is too high or too low can reduce the availability of some nutrients causing plant stress.
$16.09

Earth Juice Natural pH UP and DOWN - 2 lb each

Proper pH levels are crucial for healthy plant growth. A pH that is too high or too low can reduce the availability of some nutrients causing plant stress.
$28.85

EC Dipstick

The EC Dipstick is one of the easiest meters to use, providing the 4 most popular scales: EC, CF, 500:1ppm, and 700:1ppm!
$74.95

EcoTestr pH 2

The EcoTestr™ pH 2 has an easy-to-read display and its ergonomically designed LC display allows you to read measurements in a glance.
$72.50

Electrode Cleaning Solution - 230 ml

You can double the life of your pH tester when using Electrode Cleaning Solution on a regular basis.
$14.35

Electrode Storage Solution - 230 ml

Use storage solution to greatly extend the life of your pH meter or tester probe. This step is important for ensuring that your equipment retains its accuracy.
$9.85

Espoma Organic Garden Lime - 6.75 lb

Espoma Organic Garden Lime is pellitized for easy application and is much safer than hydrated lime.
$3.99

Espoma Organic Soil Acidifier - 6 lb

Espoma organic Soil Acidifier is an effective way to lower soil pH to its optimal range for acid loving plants such as rhododendrons, azaleas and hydrangeas.
$8.50

Future Harvest Nutradip Trimeter

When you need continuous reservoir readouts of pH, TDS and temperature, the Nutradip Trimeter is your solution.
$219.95

Future Harvest Trimeter Probe [TR 1505]

This original equipment replacement probe fits the Nutradip tri-meter.
$62.95

General Hydroponic Dry pH DOWN

We all know that the pH level in your hydroponics system is critical to optimum plant health.
$11.95 - $58.50

General Hydroponic Dry pH UP

We all know that the pH level in your hydroponics system is critical to optimum plant health.
$11.95 - $58.50

General Hydroponics pH Test Kit

The General Hydroponics pH Test Kit measures the pH level of your hydroponics nutrient solution.
$6.95

GH Liquid Pro Ph DOWN

We all know that the pH level in your hydroponics system is critical to optimum plant health. Most plants require pH levels between 5.5 and 6.8.
$11.95 - $27.95

GH Liquid Pro pH UP

We all know that the pH level in your hydroponics system is critical to optimum plant health. Most plants require pH levels between 5.5 and 6.8.
$11.95 - $27.95

GH pH 4.0 AND pH 7.0

General Hydroponics Calibration Solutions are specifically formulated for electronic pH meter calibrations and designed for hydroponic solution determinations.
$14.25 - $36.75

GH pH 4.01 Calibration Solution

General Hydroponics Calibration Solutions are specifically formulated for electronic pH meter calibrations and designed for hydroponic solution determinations.
$7.50 - $19.35

GH pH 7.0 Calibration Solution

General Hydroponics Calibration Solutions are specifically formulated for electronic pH meter calibrations and designed for hydroponic solution determinations.
$7.50 - $19.35

GH pH Control Kit

This pH Control Kit by General Hydroponics includes everything you need to check and maintain the proper pH levels for your indoor garden.
$14.95

GH pH Test Indicator Solution - 8 oz

Need a refill for your General Hydroponics pH testing kit?
$9.95

Hades Down

Nectar for the Gods Hades Down is used to lower the pH level of nutrient solution.
$22.95 - $143.95

Hanna Calibration Solutions

HANNA buffer solutions packets are perfect for single use calibration of your pH, EC TDS or Combo tester.
$1.15 - $26.95

Hanna Electrode Storage Solution - 500 mL

The electrode on a pH tester or monitor must be keep moist at all times to prevent damage to the tool.
$15.79

Hanna Instruments Champ pH Tester [HI-98106]

Model HI 98106: The Hanna Instruments Champ pH Tester is an affordable, easy-to-use pH pen that is ready-to-use right out of the box.
$46.95

Hanna Instruments Checker 1 [HI 98103]

Model HI 98103: At the cost of just a few rolls of litmus paper, you can have the industry's best pocket-sized pH tester, made by Hanna Instruments!
$36.95

Hanna Instruments Combo pH, EC/TDS/Temp [HI 991404]

Model HI 991404: A large backlit LCD continuously monitors the three most important nutrient parameters in greenhouse, hydroponics and horticultural applications.
$164.95

Hanna Instruments Combo pH/EC/TDS/Temp tester [HI 98129]

Model HI 98129: pH/EC/TDS/Temperature tester by Hanna Instruments has a completely waterproof shell that also floats. It offers high accuracy readings with dual-level LCD readout.
$191.95

Hanna Instruments DIST 5 EC/TDS/Temp tester [HI 98311]

Model HI 98311: Hanna Instruments DIST 5 EC/TDS/temperature tester is waterproof. It even floats. Gauges temperature from 0.0 to 60.0 °C or 32.0 to 140.0 °F.
$99.95

Hanna Instruments HI 1285-6 Preamplified pH and EC Probe

Model HI 1285-6 preamplified pH and EC Probe with CAL CHECK is the replacement probe for the Hanna Instruments HI 9813-6N Portable Meter.
$99.95

Hanna Instruments HI 9813-6N Portable Meter

The Hanna Instruments HI 9813-6N pH/EC/TDS/°C Portable Meter is specifically designed for agricultural applications such as hydroponics, greenhouses, farming and nurseries.
$219.95

Hanna Instruments pHep5 waterproof pH/temp tester [HI 98128]:

Model HI 98128 (pHep 5): This Hanna Instruments waterproof tester features a dual-level LCD that gauges pH level -2.00 to 16.0, and temperature from 23.0 to 140.0 °F (-5.0 to 60.0 °C).
$99.95

HI 710007 Protective Rubber Boot

The Hanna Instruments HI 710007 Shockproof Rubber Boot is designed to be used with the HI 9813-6(N) portable pH/EC/TDS/temperature meter.
$29.95

HI 73127 - Spare Electrode for Hanna Instruments Testers

The Hanna Instruments Combo pH/ES/TDS/Temp Tester Spare Electrode can be replaced to renew function and accuracy for your Hanna Instruments Brand Tester.
$58.95

Hydrion pH Test Paper Roll

Hydrion Insta-Chek pH Paper comes in a convenient plastic holder that contains a 15 foot roll of ph test paper, enough for about 1000 pH tests.
$6.25

Litmus / pH Paper Strips

Litmus paper strips are an easy-to-use alternative to check nutrient solution when you do not have a pH tester on hand.
$1.99

Martini EC59 EC TDS and Temperature meter

The Milwaukee Instruments Martini EC59 multi pocket tester measures and displays EC TDS and Temperature simultaneously on an easy to ready display.
$97.15

Martini Mi56P Replaceable Electrode

The Mi56P replaceable electrode is used with Martini pH55 and pH56 pH / temperature meters.
$42.50

Martini pH55 Waterproof pH and Temperature meter

The Milwaukee Instruments Martini pH55 Waterproof pH & Temperature tester has a large display with graphic symbols to help guide you through all operations.
$67.95

Milwaukee MW100 pH Meter

The Milwaukee MW100 portable pH meter replaces the model SM100 and is a no-frills low-cost tool that is ideal for beginners.
$93.95

Milwaukee pH600 Tester

The Milwaukee pH600 Tester is an easy-to-use, economical instrument that measures quick and reliable pH values.
$29.95

Milwaukee Portable 3-in-1 pH/EC/TDC meter [MW802]

The Milwaukee MW802 portable 3-in-1 meter allows you to measure pH, EC (conductivity) and TDS with just one instrument using a single probe. (replaces model SM802)
$199.95

Milwaukee SE600 pH/EC/TDS Combination Probe

The Milwaukee SE600 pH/EC/TDS combination probe is the replacement for both MW801 and MW802 models of combo meters.
$81.95

Oakton Multiparameter PCS Testr 35

The waterproof Oakton Multiparameter PCS Testr 35 is a pocket-sized meter used for pH, TDS and temperature readings.
$164.95

Olympus Up

Nectar for the Goods Olympus Up is a liquid lime pH booster that is also a terrific source of calcium for your garden.
$12.50 - $71.95

Rapitest Digital Soil pH Meter

The Rapitest Digital Soil pH Meter is an easy-to-use soil pH tester that determines soil acidity and alkalinity.
$10.95

Rapitest pH Soil Tester

The Rapidest Soil pH Tester is designed to give accurate pH level results with relatively little effort.
$4.50

Rapitest Soil pH Meter with probe

Ideal for testing soil pH levels of your indoor potted plants or outdoor garden areas. The Rapitest Soil pH Meter measures pH levels from 3.9 to 9.0.
$19.95

Replacement pH Electrode with BNC comm. & 2 m cable [HI 1293]

Model HI 991404: A large backlit LCD continuously monitors the three most important nutrient parameters in greenhouse, hydroponics and horticultural applications.
$69.95

Replacement pH Electrode [HI 1270]

Model HI 98103: At the cost of just a few rolls of litmus paper, you can have the industry's best pocket-sized pH tester, made by Hanna Instruments!
$24.95

Replacement pH Electrode [SE220]

This is the original equipment from Milwaukee that replaces the pH electrode on model MW100, MW101 and MW102 pH water testers.
$40.95

SaferGro pH Down - 1 pint

SaferGro pH Down is a great way to improve nutrient uptake by naturally lowering the pH of alkaline soils and hydroponic solutions.
$7.95

SaferGro pH Down - 1 quart

SaferGro pH Down is a great way to improve nutrient uptake by naturally lowering the pH of alkaline soils and hydroponic solutions.
$10.95

Sunleaves 1000 ppm (TDS) Calibration Solution - 3 oz

Calibration Solution allows you to calibrate your meter in moments.
$7.95

Sunleaves Digital 4-Way Soil Meter

The Sunleaves Digital 4-Way Soil Meter is a great tool for outdoor gardeners or indoor gardeners growing plants potted in soil.
$22.95

Sunleaves pH Electrode Storage Solution - 60 mL

Prevent damage to the electrode in your pH meter or tester during storage with a few drops of Sunleaves pH Electrode Storage Solution.
$5.95

Sunleaves pH Essential Digital Pen

Sunleaves pH Essential Digital Pen allows you to the best readings possible of your garden's pH levels. Be sure your plants have the optimal pH levels they require to grow fast and strong.
$53.95

Sunleaves pH Expert Plus Meter

With the Sunleaves pH Expert Plus, measuring the pH in your reservoir is a snap! This handheld waterproof pH meter automatically compensates for the temperature of your nutrient solution to give you an extremely accurate reading.
$103.95

Sunleaves pH Tester Kit

The Sunleaves pH Test Kit gives hydroponic gardeners a simple, foolproof method of getting fast, accurate pH readings.
$6.95

Sunleaves Soil pH Tester [SSPT500]

Monitor soil pH on a scale of 4 to 8 with the durable, easy-to-read Sunleaves Soil pH Tester.
$7.25

Sunleaves Soil Sweetener - 20 lb

Sunleaves Soil Sweetener is made from pulverized dolomitic limestone, an all-natural amendment that dissolves sour, acidic buildup in soil.
$11.95

Sunleaves SPEP505 pH Probe

This is original equipment for the Sunleaves pH Expert Plus.
$43.95

Sunleaves STEP505 TDS Probe

The STEP505 replacement probe is the same high-quality component that ships with the Sunleaves TDS Expert Plus.
$31.95

Sunleaves TDS Essential Digital Pen

Measures nutrients levels from 0-9990 ppm with accuracy to ± 0.2%.
$24.95

Sunleaves TDS Expert Plus Meter

The Sunleaves TDS Expert Plus is a highly-advanced handheld meter that measures nutrient solution electrical conductivity (EC), total dissolved solids (TDS), and liquid temperatures.
$67.95

Sunleaves Three-Way Meter [STWM500]

Conveniently test the moisture, light, and pH levels of your plants with the Sunleaves Three-Way Meter.
$8.95

Technaflora pH DOWN

Technaflora pH UP and Technaflora pH DOWN help maintain optimum pH levels for your hydroponically grown plants.
$7.25 - $14.95

Technaflora pH UP

Technaflora pH UP and Technaflora pH DOWN help maintain optimum pH levels for your hydroponically grown plants.
$7.25 - $14.95
View Order Check out