pH affects how well different nutrients dissolve in water. If the nutrients are not properly dissolved, your plants may not be getting the full benefit of the hydroponic nutrients! As there are 14 different mineral elements that plants need to grow, each plant will have a slightly different pH requirement based on which nutrients it needs the most. These target pH ranges are commonly available online.
The Hy-Gen pH adjustment kit is great for optimising the pH of your hydroponics setup so that your plants get the most out of the nutrients you're feeding them.
The kit comes with an easy to use indicator solution which allows you to take a sample of your nutrient solution and test it against a colour chart. It is accurate to 0.5 pH increments. Once you get a reading, you can use the pH up or down solutions to adjust the pH accordingly - for most systems a pH between 5.8 and 6.5 is good.