-50% on a selection of fish food
In hydroponics, roots absorb nutrients best when the solution sits between pH 5.5 and 6.5. pH down lowers a solution that is too alkaline, the most common case with hard water; pH up corrects a solution that has become too acidic. The liquid versions can be dosed drop by drop, while the powder version is more concentrated and more economical.
Always add the adjuster in small doses, stir, then measure again. In aquaponics, pH is regulated differently, see Regulating pH in an aquaponic system.













