Bluelab pH PenThe ultimate handy solution for measuring pH! Plants get their nutrition from minerals but they can only get all the right minerals they need if certain conditions are right. A key factor that affects food uptake is whether your solution is acid or alkaline. We measure this in pH. The Bluelab pH Pen is the latest innovation for hand held meters. It provides a compact quick and handy way to manage the success of your crops to ensure maximum uptake of