The pH Buffer Solution 4.01 and 6.86 are essential tools for maintaining the optimal pH levels in your hydroponic system. These calibration solutions, made with phosphate ingredients, have a long-lasting effectiveness of up to 8 weeks and come in a convenient 250ml volume. Suitable for all-purpose use, these pH buffers are lightweight at 0.1kg and ideal for keeping your plants healthy and thriving in a pH-controlled environment.
eBay