Orange pH Minus Bloom is used to decrease the pH of the substrate or the feeding water in a hydroponic system.
To do this, a (59%) solution of phosphoric acid is used.
This substance acidifies the water or substrate and also adds a decent amount of phosphorus to it. Because of this latter part, one should be careful when dosing pH Minus Bloom in the water, and only use it during the flowering phase. The nutrient profile of the water (and thus the diet that the plants receive) changes when adding pH Minus Bloom. When used in combination with the Orange King or Complete products, the amount of pH Minus Bloom that is added to the feeding water will rarely exceed safe levels.
The King and Complete products are developed to acidify and buffer the water to optimal levels.