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Bluelab Guardian Monitor
Bluelab Guardian Monitor
List Price: $364.00
Our Price: $319.00
Savings: $45.00

Seasonal changes, sunlight hours, wind, inherent plant growth; from vegetative to fruiting; are all influencing factors to plant growth success. But more importantly, these parameters change the plants uptake and need of water and specific nutrient elements. The Bluelab Guardian is a constant indicator of the desired levels of EC, pH and temperature, enabling the grower to optimize these parameters as the crop progresses through each growing phase. The Bluelab Guardian removes the complexity of how each parameter relies on each other for outstanding growth. Our innovative monitor is a new method to help guard the success of your crops with immediate and accurate results. A flashing display lets you know if one parameter moves away from the ideal, allowing you to make the required adjustments quickly and effectively.


  • Adjustable brightness display
  • Large easy to read displays
  • Plant Safe' green LED display
  • Selectable values for conductivity and temperature Simple push button pH calibration
  • No calibration required for conductivity and temperature
  • Silent alarm for both high and low settings
  • Settings retained when power lost (non-volatile memory)
  • Temperature compensate
  • International power supply
  • Water resistant design

2 year guarantee (6 months for pH probe)

Bluelab Combo Meter
Bluelab Combo Meter
List Price: $308.00
Our Price: $260.00
Savings: $48.00

The Bluelab Combo Meter is a conductivity, pH and temperature meter all  in one. It comes with a pH probe and conductivity and temperature probe,  which are simply placed into the solution and the selected reading is  displayed on screen. The Bluelab Combo Meter is portable and does not  require a power supply. Calibration of the pH is very easy, using the  push buttons on the meter and fresh Bluelab calibration solutions.  Conductivity and temperature do not need to be calibrated as this is  locked in during manufacture. Select display options for temperature (C  or F), and EC, CF, TDS or ppm (700).antee.
Hanna GroChek pH/EC/TDS/Temp - HI9813-6N
Hanna GroChek pH/EC/TDS/Temp - HI9813-6N
List Price: $283.95
Our Price: $220.00
Savings: $63.95

HI 9813-6N is a versatile, water resistant multiparameter portable meter specifically designed for agricultural applications such as hydroponics, greenhouses, farming and nurseries. It features an extra large LCD that clearly displays the parameter being measured as well as calibration instructions. Calibration is fast and easy with knobs located on the front panel of the instrument. HI 9813-6N is a pH/EC/TDS meter designed for simplicity of use in taking pH, mS/cm, ppm and temperature in the °C scale measurements. HI 9813-6 includes all the features of the HI 9813-5 while incorporating our exclusive CAL CHECKTM feature. CAL CHECKTM allows the user to easily check the probe calibration status at any time. Both instruments utilize the HI 1285 series pH/EC/TDS/temperature probe. This probe features a fiber junction and gel electrolyte making it ideal for fertilizer solutions.


Water resistant
On-screen user guides-Save time with on-screen calibration guides
BEPS (Battery Error Protection System) alerts the user in the event that low battery power could adversely affect readings
Switch parameters at the touch of a button
Automatic Temperature Compensation- For pH and conductivity
Simple calibration-Dials located on the front panel makes calibration quick and simple, even for non-technical users
Battery % displayed on startup
Fast response probe included

Nutradip Tri Meter (pH, PPM, & Temp)
Nutradip Tri Meter (pH, PPM, & Temp)
List Price: $233.95
Our Price: $195.00
Savings: $38.95

The Nutradip Tri-Meter combines the technology of the pH and TDS meters and addresses an additional key factor in hydroponic growing, the temperature. Temperature in a nutrient solution is often wrongly overlooked. The temperature variance in a growing operation can significantly restrict the growth and yield of the plant(s).
With no effort at all, reliable, continuous reading of TDS, pH, and temperature can simultaneously be monitored and correct levels can easily and reliably be maintained.

Hanna Waterproof Combo Meter - Black
Hanna Waterproof Combo Meter - Black
List Price: $203.95
Our Price: $160.00
Savings: $43.95

The Combo Waterproof Tester takes highly accurate readings of temperature, pH, EC and TDS. The unit is protected by a strong plastic waterproof casing, and comes equipped with a replaceable pH electrode, salt-resistant stainless steel EC/TDS and temperature probes, electrode replacement tools to make maintenance simple, batteries and a self-check feature. A low-battery alert ensures proper functioning and the unit also automatically notifies users when to take and when to freeze the reading for accurate measurements; this tester also features automatic temperature compensation. EC/TDS calibration is 1-point automatic, and pH is 1 or 2-point with two sets of memorized buffers; pH 4.01, 7.01 and 10.01 or 4.01, 8.68 and 9.18. The Combo Waterproof Tester reads EC with a range of 0-3999 µS/cm and resolution of 1µS/cm, TDS with a range of 0-2000ppm and resolution of 1 ppm, pH with a range of 0.00-14.00 and resolution of 0.01, and temperature with a range of 0.0°-60.0°C and resolution of 0.1°C. or 32.0°-140°F and resolution of 0.1°F. The combination of quality, features and portability makes this tester a great choice.

  • Dual-level LCD
  • Replaceable pH Electrode Cartridge
  • Automatic Caliibration
Bluelab Truncheon Meter - PPM/TDS, CF, EC
Bluelab Truncheon Meter - PPM/TDS, CF, EC
List Price: $140.00
Our Price: $109.20
Savings: $30.80

You can easily measure and maintain nutrient strength levels with the waterproof Bluelab Truncheon Meter. Truncheon reads in EC (0.2-3.6), CF (2-36), TDS/ppm 500 (100-1800) and ppm 700 (140-2520). Accurate within ± 4% of reading with a resolution of 0.1 EC, the Truncheon runs on three AA alkaline batteries and comes with a five-year manufacturer's guarantee.

Hanna Waterproof EC / TDS Meter - Blue
Hanna Waterproof EC / TDS Meter - Blue
List Price: $130.95
Our Price: $100.00
Savings: $30.95

The Waterproof EC/TDS Tester is an easy-to-use, convenient meter. Graphite electrodes ensure accuracy, and are easily replaced with a new cartridge. This tester comes with a probe, batteries and electrode replacement tool to make maintenance easy. Stainless steel temperature probe provides fast and accurate measurement. The unit automatically figures calibration and temperature compensation, but the EC/TDS conversion factor and temperature coefficient are adjustable. The dual-level LCD display shows EC and TDS as well as F. or C. Unit features a prompt telling the customer when to take a reading and also when to freeze the display. The battery lasts 100 hours, and the unit automatically shuts off after 8 minutes. Range: EC - 0 to 3999 µS/cm; TDS - 0 to 2000 ppm. Accuracy: EC ±2% full scale, TDS ±2% full scale, temp ±5° C or ±1° F. This tester combines the convenience, accuracy and quality that customers need.
  • Dual-level LCD
  • Replaceable Graphite Electrode Cartridge
  • Automatic Calibration
Bluelab pH Pen
Bluelab pH Pen
List Price: $112.50
Our Price: $88.00
Savings: $24.50

The Bluelab pH Pen is a handy option for hobby and small scale hydroponic growers. Maintaining proper pH levels is key in raising healthy, fruitful plants, and this pen accurately measures both the pH and temperature in your hydroponic system. It also features selectable units for ˚C and ˚F, a backlit LCD display, double junction probe, successful calibration indicator, hold function, low battery warning, auto off function, automatic temperature compensation, and is fully waterproof. This pH Pen has a range of 0.0 – 14.0 pH and 0-50 ˚C or 32-122 ˚F, and an accuracy to ±0.1 pH. It requires one AAA battery (included), and has a 12 month manufacturer’s warranty.

Bluelab PPM Pen
Bluelab PPM Pen
List Price: $94.00
Our Price: $74.00
Savings: $20.00

The Bluelab ppm Pen measures conductivity and temperature and is a great way to ensure plants are receiving the proper amounts of nutrients. This pen features a backlit LCD display, optional calibration and a successful calibration indicator, a hold function, low battery warning, auto off function, automatic temperature compensation, and is fully waterproof. It operates in units of 500 or 700 ppm and has a range of 0-5000 ppm or 0-7000 ppm, and accuracy to ±50ppm or ±70ppm. Requires one AAA battery (included) and has a 12 month manufacturer’s warranty.

Milwaukee pH600 Tester
Milwaukee pH600 Tester
List Price: $34.50
Our Price: $30.00
Savings: $4.50

Milwaukee's pH600 Tester is an easy-to-use, low-cost instrument that measures pH values quickly and reliably. It features one-point manual calibration, ±0.1 pH accuracy and a range of 0.0 to 14.0 pH. The pH600 includes a calibration screwdriver, batteries and instructions. Protected by 30-day manufacturer’s warranty.

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