In a honing system for producing a light-scattering surface on a photoreceptor substrate for use in xerographic printers, a constant concentration maintenance device is employed to drain an appropriate amount of liquid from a honing slurry to match the amount of liquid added during rinsing of the photoreceptor substrate. The constant concentration maintenance device is mechanically effected by vibrations in the mixing apparatus of the honing system, facilitating separation of the liquid an solid parts of the slurry. Delay between honing and rinsing is eliminated through use of the same honing booth for both operations.