The Bluelab Grower’s Toolbox combines the essential tools to easily manage crops by measuring the pH, conductivity (ppm) and temperature of the nutrient solution. Learn the hydroponics basics with the Grow Book. Keep growing with the ultimate handy team, the Bluelab pH Pen and Bluelab ppm Pen. Create the best nutrient environment for plants’ growth with these clever little pens that make it easy to measure the nutrient uptake (pH), the amount of food available (ppm) and the solution temperature. The Bluelab Probe Care Kit makes maintenance easy to maximize the life and accuracy of the pens’ probes. With these tools and essentials in one value added pack, the Grower’s Toolbox is a complete simple crop management system that helps get it right, from the start.