# For convergence, add a redox buffer in the input file: 
SOLUTION_SPECIES 
    H2O + 0.01e- = H2O-0.01 
    -log_k -9 
SOLUTION 1
pH  6.0
Na  1.236; K    0.041; Mg   0.115; Ca   0.067
Cl  1.467; N(5) 0.058; S(6) 0.085; Alkalinity 0.26
O(0)  0.124
EQUILIBRIUM_PHASES 1
Goethite  0 2.5e-3
FeS(ppt)  0 0
Pyrolusite  0 4e-5
REACTION 1
C; 0.572E-3 in 26 steps
INCREMENTAL_REACTIONS true
PRINT; -reset false
USER_GRAPH 1
 initial_solutions true
 headings C O2 NO3 Mn Fe SO4 S(-2) C(-4)
 axis_titles "Carbon added, mmol/L" "Concentration, mol/L"
 -start
 10 graph_x step_no * 0.572 / 26
 20 graph_y tot("O(0)")/2, tot("N(5)"), tot("Mn(2)"), tot("Fe(2)"),\
    tot("S(6)"), tot("S(-2)"), tot("C(-4)")
 -end
END