Fe3+ +3HCO3-=Fe(OH)3+CO22Fe3+ +3H2O+ 3CO32-=2Fe(OH)3+3CO2NH4++ AlO2-+ 2H2O = Al(OH)3 + NH3.H2O
2Fe3++3CO32-+6H2O=2Fe(OH)3↓+3CO2↑Fe3++3HCO3-=Fe(OH)3↓+3CO2↑NH4+ + AlO2- + H2O = Al(OH)3↓+NH3↑