How to see the effect of an increased pH on a composition of water

[akaess]

Hello,
I am trying to see what in my concentrate stream may precipitate at an increased pH but I do not remember how to do this in PHREEQC. Below is the beginning of my code.
Thank you for the help.

DATABASE c:\phreeqc\database\WATEQ4f.dat
SOLUTION_MASTER_SPECIES
    SiO2  SiO2(aq)  0.0  Si  60.0843

SOLUTION_SPECIES
    SiO2(aq)  =  SiO2(aq)
    log_k  0.0
SOLUTION_MASTER_SPECIES
    CO2  CO2(aq)  0.0  C  44.01

SOLUTION_SPECIES
    CO2(aq)  =  CO2(aq)
    log_k  0.0
SOLUTION 1
-units   mg/l
-temp 14.5
pH   7.93
Alkalinity   240.54 as HCO3
Na   402.610
K   48.728
Ca   15.345
Mg   13.555
Cl   581.687
S(6)   0.821
N(-3)   0.242
Fe(2)   0.021
P       0.237 as PO4
Ba      0.198
Sr      2.380
As(+5)  0.31958
SiO2    15.007
B       1.201
Mn(2)   0.021
Ba      0.198
CO2     6.47

END

USE SOLUTION 1
REACTION
pH 9.8

[dlparkhurst]

Do not add the SiO2 species. Wateq4f.dat has the equivalent species H4SiO4.

Do not use SiO2 in the SOLUTION definition. Use Si.

Do not use CO2 in the SOLUTION definition. Alkalinity and pH are sufficient.

Add NaOH in the REACTION in increments,

Code: [Select]

REACTION 1
NaOH 1
xx moles in nn steps

Alternatively, you can fix the pH with the following:

Code: [Select]

PHASES
Fix_H+
H+ = H+
log_k 0
END
...
EQUILIBRIUM_PHASES
Fix_H+  -9.8 NaOH 10