KALIX Humic Acid is a highly concentrated (57%) formulation of water soluble organic acids that are found naturally in soil matter. Humic acid is a carbon source that contributes to multiple metabolic processes in plants and can be particularly beneficial when used in the root zone. Humic Acids are not a single compound, they are a collection of different compounds all with similar characteristics. KALIX Humic Acid is a natural chelator and suitable for use in conjunction with all nutrient and feeding programs. 25 Lb bag.