Wick mushrooms and carbons up
A mushroomed wick means the wick is delivering more fuel than the flame can burn cleanly. The carbon ball is unburned wax and FO. It causes sooting and is a fire-safety flag.
Why this happens
A mushroom is unburned carbon and fragrance the wick delivered faster than the flame could combust. It glows red because it's still hot enough to smoulder, which throws micro-sparks into the room and coats the vessel rim in soot.
Likely causes
- Wick is over-sized for the vessel.
- Fragrance load is too high or contains heavy resins.
- Wick brand mismatch (e.g. zinc-cored wick in a clean-burning blend).
How to diagnose
- Photograph the wick after a 2-hour burn. A small mushroom (2 mm) is normal; anything larger is over-wicked.
- Check for soot deposits on the inside of the vessel rim.
Change sheet · next batch
Fill in what you know. The change sheet below re-orders so the delta most likely to help your specific batch floats to the top.
Reduce fuel delivery so combustion stays complete.
Heavy resins and vanillin overload the flame.
Removes the carbon ball before each burn.
Take action
- Visible soot or black smoke
Black trail off the flame, deposits on the vessel.
- Flame jumps, flickers, or pops
Unstable flame, often paired with crackling.
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