How acidic is the water? And how about the soil? Examine the acidity of the soil, your (home made) yogurt, soda or the water in your area using something as simple as red cabbage. Download and print the instructable below, gather your ingredients and get started!
A4 Instruction leaflets
Download the DIY instructions above. Print these double-sided (always the most sustainable choice) on plain paper. Now fold the paper twice, leading to a small booklet with the title in front. Ready!