AsturShadow I use Las Jaras Nestlé Aquarel spring water (30 cents per liter). It has an EC of 0.05 mS and a pH of 5.3. When I add Atami CalMag and Top Crop Top Auto during its different phases, the pH is perfect, being 6 or 6.2 (EC 0.8) during growth and 6.6 or 6.7 during flowering (EC 1.5).