General Hydroponics® GH Hardwater Flora Micro Gallon – 6923107336373

If your tap water is over 200 ppm (or contains Calcium above 70 ppm), use Flora Micro® Hardwater. If your water contains 30 to 50 ppm Calcium, you can mix our original Flora Micro® with Flora Micro® Hardwater to create a perfect Micro blend for your plants.