Open Fire Opti Myst - Wood Burner Smell ?

[utterlydiy]

I have a Opti-Myst open fire with its vapour smoke effect and glowing logs etc.

Although the fires effect is soothing and warming to look at with the brain thinking its a traditional burning fire.

Its bland, any ideas if there's anything that could be added to the water tank to give a wood or coal burning smell effect in its smoke.