When using water as a solvent, a reference system (W) of either solute 1 or 2 is constructed by including the 50 closest water molecules to either of the chromophores in the quantum region with the remaining water molecules treated by the TIP3P water model. To study the effect of demoting solvent molecules from the QM region to either one of the classical potentials described above, several smaller systems based on W are constructed. Three models, W1, W2 and W3 are constructed by replacing the 50 water molecules with TIP3P, WAT and M2P2, respectively. Additional models based on W1, W2 and W3 were also constructed where the water molecules thath are hydrogen-bonding to the solutes are included in the QM region. For all W1, W2 and W3 the remaining solvents surrounding the 50 specified solvents are still treated as TIP3P.