Correct rootzone pH is essential for optimum nutrient availability. Atlas Scientific has really gone above and beyond with their peristaltic pumps and their pH probe that can be permanently submerged. This is a more intermediate/advanced project for the Arduino user, but very doable and user friendly. We are currently testing it on the wall garden. Soon we will move it to the greenhouse. Don’t feel like you have to have automated pH contol. For years I only used a liquid color indicator test and dosed pH adjuster using a pipet. It works fine. However, this is a really neat alternative.
Click here for Project Tutorial
Final Test before Installation
Breadboard Test
Comments: This was as really cool little project. I installed everything in a weatherproof junction box. I did this because I want to use it in the greenhouse where there can be a lot of condensation and moisture. On the pH up and down bottles, I installed a cable gland and an aquarium air hose backflow preventer. This lets air into the bottle but not out, preventing a vacuum. I did this to keep the moisture in the junction box down, and the corrosive pH adjusters safely in their containers. It might be a bit overkill, not sure yet. When the junction box is closed, some heat is generated from the electronic components. It doesn’t seem to be a problem, but it might become one it used in an already hot environment, like the greenhouse. I’ll keep you updated. Rembemer, this is your project and you can build it anyway you like. You don’t have to put everything in a junction box.