Balancing the nutes in hydroponic solution is essential. If the nutrient solution is too concentrated the solution will not absorb the water and if the solution is too weak the plants would be left unnourished. Visual indications are often your first clue that something is wrong with your nutrient solution. Watch your plants for signs of stress, including wilting, leaf color that is either too dark or too light, and woody or stunted growth. Make sure your meters are calibrated correctly before using them. pH meters are notorious for losing their calibration, so keep a liquid test kit or pH strips on hand to double-check your results.
Measuring the nutrient concentration
An ideal way of measuring the nutrients is by checking the Electric Conductivity (EC) of the solution. An electric conductivity helps us find the quantity of nutrients present in the water. Before adjusting the nute values, remember that you should read manufacturer’s instructions carefully and use the pH and EC meters accordingly. Now to begin with, take the base reading by inserting the EC meter’s probe in the solution. Compare the reading with an ideal EC chart for hydroponics.
If the EC reading is too high, dilute the solution by adding water to it. If the EC reading is too low, add concentrated nutrient solution to the reservoir. Mix well and let the solution rest for 10 minutes, then re-test. Repeat this step until EC levels match the reading shown in the chart.
Measuring the pH
pH levels in hydroponics are the indicators to decide whether a solution is acidic or alkaline
- Paper test strips: They are impregnated with a pH sensitive dye which changes color when dipped into the nutrient solution. The paper strip is then compared to a color chart to determine the pH level of the solution being checked. These test strips are inexpensive, but they can be hard to read, because the colors differences are subtle.
- Liquid pH test kits: Popular and preferred by Hobby gardener. These liquid test kits work by adding a few drops of a pH sensitive dye to a small amount of the nutrient solution and then comparing the color of the resulting liquid with a color chart.
- Digital Meters: These meters come in a huge array of sizes and prices. The most popular type of pH meter for the hobby gardener is the digital pen that dips the electrode into the nutrient solution for a few moments and the pH value is displayed on an LCD screen.
If the solution is to acidic (the pH is too low), add one to three drops of phosphoric acid to the nutrient reservoir. If the solution is too basic (the pH is too high), add one to three drops of potassium hydroxide. Mix well and let the solution rest for 10 minutes, then re-test. Continue to adjust until the pH is between 6.0 and 6.5.
Re-check the EC and pH levels of your nutrient solution every three to five days to maintain ideal conditions for your plants. If you suspect growth problems, check and adjust more frequently.