For those of you who want to check the pH levels of your nutrient solutions - without having to splash out on a digital meter - there is the option of a manual test kit.
Simply take a sample of your solution, add a couple of drops of the indicator and then check against the colour chart supplied with the kit. Whilst not as accurate as a digital pH meter, these kits are an excellent choice for growers on a budget!
pH Test Kits are available in the following ranges: