Aqua Flow System for The Grinder (Techniglass) - No More Sponges! - this works great. Aqua Flow System. A flow system for grinders, made of proprietary brush bristles attached to a highly rigid polymeric holder. It allows water to flow freely through the bristles, providing continuous water to the grinder bit while simultaneously washing away sludge. Eliminates sludgy sponges. TECHNIGLASS 2004