I have been trying to update the thermo database for both Mo and W speciation. I have had no problems adding Mo+++, MO4-- and a variety of Mo aqueous species and minerals. This is not the case for Tungsten. I succesfully added W to the elements, but upon adding WO4-- to the basis species (see input below), I get an error message. I've chosen to add WO4-- into the basis, as opposed to the aqueous species, since this is the main basis used in the various aqueous and mineral reactions. WO4-- charge= -2.0 ion size= 1.4 A mole wt.= 247.8376 2 elements in species 4.