When cleaning a glass water pipe with a brush, the glass surface will be scratched again and again - even if you can't see it at first.
This is, on the one hand, aesthetically not pleasing and, on the other, it will reduce the life-span of your pipe.
The surface is no longer smooth and dirt can collect more easily in these fine scrathes.
Also, as the surface is hurt, the pipe will breal more easily.
For these reasons we recommend our biodegradable ROOR cleaning agent on alcohol basis, as it enables the cleaning of the pipe without a brush in a couple of minutes.