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This calculator provides the recommendations for the amount of acid to add to irrigation water in order to modify the pH and alkalinity levels. In addition, the calculator provides the amount of added phosphorus, nitrogen, and sulfur that the corresponding acids will provide, plus an economic comparison of each acid. For more information on the safe use of acid check out this
The pH of your sample:
The alkalinity of your sample:
Target alkalinity or pH:
(must be below pH 7.2)
Alkalinity ppm HCO<sub>3</sub>
Alkalinity ppm CaCO<sub>3</sub>
(set at 2 meq/L alkalinity for most crops)
All acid types
All fields on this form are required!
Additional information regarding cost comparisons of various acids as well as the safe use of acids can be found on the tabs at the top of the page.
This spreadsheet was originally developed in 1995 by a research team at North Carolina State University (Douglas A. Bailey, Paul V. Nelson, and William C. Fonteno) and Purdue University (P. Allen Hammer and Brian E. Whipker). This version was revised in 2009 by Brian A. Krug of the University of New Hampshire and Brian E. Whipker of North Carolina State University.
A scientific description of the alkalinity calculator can be found at: Whipker, B.E., D.A. Bailey, P.V. Nelson, W.C. Fonteno, and P.A. Hammer. 1996. A novel approach to calculate acid additions for alkalinity control in greenhouse irrigation water.
Comm. Soil Sci. Plant Analysis 27:959-976.