pH influences several factors that play an important role in plant growth. These factors include nutrient availability and nutrient toxicity. Most minerals and nutrients are more available to plants in acidic environments than in neutral or alkaline environments. While most plants can survive a pH range of 5.0 to 7.5, each plant has a specific pH value in which it optimally absorb nutrients. Beyond a certain pH value, nutrients become unavailable to plants. This is due to the solubility of minerals and nutrients. Therefore, pH has a huge impact on the solubility of fertilizer. If the nutrient solution is not the correct pH balance, some nutrients will precipitate out of solution (i.e. not dissolved) and can no longer be absorbed or used by plants. At a pH above 6.5, some nutrients such as iron, will begin to precipitate out of solution. For optimum nutrition uptake in a hydroponic system it is important to maintain a pH range of 5.5 to 6.5.
Hanna offers a wide range of equipment and accessories to measure and monitor pH.
Below are the most common products used hydroponic pH measurement.
A variety of portable meters are available to measure pH. Many portable meters are made specifically for the hydroponics market. These meters have CAL Check functionality with some of them using specialized pH probes that will identify a probe that have damage to the internal glass stem or hairline fracture in the glass sensing bulb. A standard pH electrode will display a frozen reading of pH 7 when there is damage. The meters with CAL Check will display a reading close to pH 4. This is very beneficial to users that perform a single point calibration to pH 7 and expect to have results that are close to pH 7.
Also included in this category are multiparameter meters that can measure conductivity and/or TDS.
A variety of testers are available including a version that allows for the direct pH measurement in rockwool and other soiless media.
The monitoring & control of nutrient solutions is critical to successful propagation and optimization of plant growth. Different plant species have an optimal pH for nutrient uptake and growth.
Monitors offer the ability to continuously measure and display pH. Multiparameter versions are also available that display EC and/or TDS in addition to pH.
Benchtop meters include a multiparameter photometer version made for measuring nutrients in a solution. The benchtop photometer hasa digital probe input that allows it to be used to take a pH measurement with a standard pH electrode.
In this category are the replacement pH probes for hydroponic pH and multiparameter meters.
In this category are pH calibration buffers including our GroLine buffers that are supplied complete with a certificate of analysis. The pH calibration buffers are available in a variety of sizes from single use sachets to bottles.
Also included in this category are the Quick Cal solutins used with some of the hydroponic pH meters. These solutions are formulated for single point calibration of both pH and EC.
Maintenance solutions include both cleaning, storage, and probe refill solutions.
Cleaning solutions are available that are made specifically for agricultural use.
Accessories include shockproof rubber boots used with the portable meters. These boots give additional protection from accidental drops and provide for a more tactile feel when holding the meter.