pH Down Bloom by Advanced Hydroponics of Holland is a pH correction liquid for growing marijuana in soil, coconut fiber or hydroponic media. The pH is the measure used to determine the level of acidity (low pH) or alkalinity (high pH) of a solution, in this case it is irrigation water with or without fertilizers and / or additives. Marijuana plants need to have the nutrients available within a pH range that will vary depending on the growing medium we use, if we are growing or flowering, variety, type of water, etc. pH Down Bloom by Advanced Hydroponics of Holland, thanks to its stabilizers, will lower the pH level and keep it stable to the desired extent, especially suitable for the flowering phase.