If I remember correctly, fulvic acid is a chelater that aids the breakdown and uptake of nutrients. What does fulvic to to ph?
A few things to know about most commercially extracted fulvic acids. It should be some shade of yellow like apple juice, if it is dark and black you have a humic (and fulvic) product. Most water extract fulvic acids without any additives or extractants are around pH 3.0. Some manufacturers will use low grade ore and extract with phosphoric or citric acid this give it a low pH but in truth has very little fulvic. If you see any phosphate on the analysis (over 1% P) you typically are getting a cheap fulvic. Technically speaking fulvic does not chelate as much as complexes, but that is semantics really for your purposes. Fulvic solutions have a very high cation exchange capacity which helps to store and increase the availability of nutrients. Moreover, fulvic can affect plasma membrane H+ATPase activity and nutrient uptake like nitrate. So to answer your question directly, Keep your eye on pH, overly acidic solutions can cause problems like aluminum toxicity. Because of the increased nutrient availability a solution that was not "hot" can become so just by adding fulvic to the solution, which increases that availability of the nutrients that might cause burn. Last fulvic is a natural component of all decaying plant mater, fulvic is abundant in media such as peat and compost. You would find rich tropical areas with significant amounts of fulvic in the soil. These areas thrive rather than burn from the high amount of organic acids. To recap the fulvic is not causing burn, but the pH of the fulvic may cause toxicity and/or increase availability of salt based nutrients and cause burn. Hope that helps.
*Yes, I am a professional in the field of fulvic manufacturing.
