Default sorting Sort by popularity Sort by average rating Sort by latest Sort by price: low to high Sort by price: high to low View: 12 24 All Growth Technology, Nutrient & Additives, Nutrient & PH Control, Other AdditivesGrowth Technology Hydroponic PH Down £4.99 – £29.99 Plants in hydroponic systems function best with a nutrient solution pH of between 5.8 up to 6.2.Select options