Commercial ice making machines greatly improve the quality of ice by using flowing water. The water runs down a surface that is constantly at 32 degrees F since only pure water without impurities will freeze at this temperature on a surface. Water with impurities usually requires lower temperature to freeze and will continue to wash down the surface and through the drain of a commercial ice making machine. Air and undissolved solids will be washed away to such an extent that in horizontal evaporator the water has 98% of the solids removed to guarantee rather hard virtually pure, clean ice. In vertical evaporators the ice is much softer, more so if there are actual individual cube cells. Commercial ice making machines can produce different shapes of ice such as flake, nugget, crushed, cube, tube, therefore commercial ice making machines are categorized as flake ice making machines, cube ice making machines, tube ice making machines, block ice making machines , plate ice making machines and ice crushed machines etc..