PH control kit Contains Ph Up, Ph Down and Ph Test indicator Add a little Ph Up at a time when your nutrient pH is too low in order to raise the pH to the proper level Ph Down uses food grade Phosphoric acid to lower the pH to the proper level Ph Test Indicator is added to the test tube with the nutrient and observe the coloration of the liquid in the test vial Use 3 drops per 5mL of solution 1 fl oz.