formaldehyde...???

[lachance88]

I have a demi-john with formaldehyde scum in it from the late 20's........ What is the gentlest way to start trying to clean this thing? I'm kinda anti-chemicals........ but not UNopposed to suggestions? Thanks,
Kathy

 

[Bottle tumbler]

if it's only dry stuff, add dawn, some copper bbs and swish around. do this over the whole inside, it may help
www.bottletumbling.com
rick