Brushes for bowl and HMD

Dedicated brushes match the size and shape of bowl holes and HMD vent channels. A regular toothbrush works as a backup, but it's too thick for the smaller holes and can chip the inside of a ceramic or clay bowl. A purpose-made brush does the job more thoroughly and more safely. The cost difference is small, the difference in how clean the bowl actually gets is bigger than you'd expect.

Ceramic and clay bowls need a soft-bristle brush. Clay is porous and easy to score. Soak the bowl in warm water for 5 to 10 minutes before brushing to soften the molasses residue. Use circular motions, since that works better than the straight in-and-out scrub, especially for cylindrical holes where the residue clings to the sides. Stiff brushes are for steel HMDs only, and never for ceramic bowls under any circumstance.

Once a week, or whenever you can see visible deposits in the vent slots. Clogged vents kill airflow and noticeably drop session quality. The HMD is still doing its job, just badly. For daily ash removal, a soft brush or dry cloth is enough. Hard metal brushes are fine on stainless steel HMDs but not on anodized aluminum, since they strip the protective surface and leave the part more vulnerable to corrosion and residue buildup.