Changes in version 2.1.0 (2021-05-01) New features - Allow for accounting of SiO2(OH)2 ion if second dissociation constant for sillicic acid is given. Bug fixed - Softare crashed when using [CO3--] and TA pair with specific input values Changes in version 2.0.0 (2021-03-09) Creation from FORTRAN version 2.0 of solveSAPHE (not yet published as of April 2021) New features This version adds processing of new pairs of variables beside the initial one: DIC and Total Alkalinity New pairs are : [CO2] and TA |HCO3-] and TA [CO3--] and TA Changes in version 1.0.0 Creation from FORTRAN version 1.1 of solveSAPHE (December 16, 2020) This version is available at: https://zenodo.org/record/4328965