def dens_floc_init(ConcAluminum, ConcClay, coag, material):
    """Return the density of the initial floc.

    Initial floc is made primarily of the primary colloid and nanoglobs.
    """
    return (conc_floc(ConcAluminum, ConcClay, coag).magnitude
            / frac_vol_floc_initial(ConcAluminum, ConcClay, coag, material)
            )
Return the density of the initial floc.

    Initial floc is made primarily of the primary colloid and nanoglobs.