Bluelab Combo Meter - 6.5ft Probe Cable

Bluelab Combo Meter — Portable All-in-One pH, EC & Temperature Meter with 6.5 ft Probe Cable

The Bluelab® Combo Meter is the go-to portable testing instrument for hydroponic growers who need accurate, reliable measurements of pH, electrical conductivity (EC), and temperature — all in a single handheld device. Whether you're checking reservoir conditions, testing runoff, or monitoring multiple grow sites, the Combo Meter delivers fast, precise readings with no external power supply required, making it ideal for use anywhere in your facility.

The 6.5 ft probe cable gives you the reach to test deep reservoirs or hard-to-access containers without straining or repositioning the meter. The large, backlit LCD display is easy to read in low-light grow room conditions, and push-button operation lets you cycle through conductivity scales — CF, EC, PPM 500, and PPM 700 — at the touch of a button. Conductivity and temperature are factory-calibrated and require no field calibration. pH calibration uses a simple two-point process with a 30-day calibration reminder indicator to keep your readings accurate.

The Combo Meter features a replaceable double-junction pH probe for extended service life, over-range and under-range indicators, a low battery indicator, and an auto-off function to conserve battery life. Two AAA alkaline batteries are included.

Key Features

• Measures pH, EC (conductivity), and temperature in one portable device
• 6.5 ft probe cable for deep reservoir and hard-to-reach testing
• Conductivity scales: CF, EC, PPM 500, PPM 700 — switchable at the touch of a button
• Large backlit LCD display for easy reading in low-light environments
• No external power supply required — runs on 2 AAA batteries (included)
• Factory-calibrated conductivity and temperature — no field calibration needed
• Simple two-point pH calibration with 30-day calibration indicator
• Replaceable double-junction pH probe
• Over/under-range indicators, low battery indicator, auto-off function

Frequently Asked Questions

What does the Bluelab Combo Meter measure and why do I need all three parameters?

The Bluelab Combo Meter measures three critical parameters of your hydroponic nutrient solution: pH (acidity/alkalinity), electrical conductivity (EC, which indicates nutrient concentration), and temperature. All three are interdependent — pH affects nutrient availability, EC determines whether plants are receiving the right nutrient dose, and temperature influences both pH readings and plant metabolism. Monitoring all three with a single portable instrument gives growers a complete picture of reservoir health at any point in the growing cycle, enabling faster and more accurate adjustments.

Does the Bluelab Combo Meter need to be calibrated?

Conductivity and temperature measurements are factory-calibrated and do not require field calibration. pH calibration is required and uses a simple two-point process with pH 7.0 (buffer) and pH 4.0 (slope) reference solutions. The meter includes a 30-day calibration indicator that reminds you when pH calibration is due, helping you maintain measurement accuracy without having to track calibration dates manually. Bluelab recommends calibrating the pH probe at least once a week in active growing environments.

What conductivity scales does the Bluelab Combo Meter support?

The Combo Meter supports four conductivity scales switchable at the touch of a button: CF (conductivity factor), EC (electrical conductivity in mS/cm), PPM 500 (parts per million using a 500 conversion factor), and PPM 700 (parts per million using a 700 conversion factor). This flexibility makes the Combo Meter compatible with nutrient programs and growing guides that use any of these common measurement conventions, without requiring separate instruments or manual conversion.

Why does the Bluelab Combo Meter have a 6.5 ft probe cable?

The 6.5 ft probe cable allows growers to test deep reservoirs, large containers, or hard-to-reach nutrient solutions without repositioning the meter or straining to reach the surface. This is particularly useful in commercial hydroponic setups where reservoirs may be large, elevated, or positioned in tight spaces. The extended cable keeps the meter body dry and accessible while only the probe enters the nutrient solution.

Where can I buy the Bluelab Combo Meter?

The Bluelab Combo Meter (6.5 ft probe cable) is available through Seres Ag, a professional hydroponic and CEA equipment supplier serving growers across the United States. Purchase directly at seresag.com. Seres Ag offers expert product support, competitive wholesale and retail pricing, and US-wide shipping. For bulk or wholesale inquiries, contact the Seres Ag team through the website.