When carboys are store wet and empty for a long time they will develop
calcium water stains inside. Subject the hardness of your water the removal
of these stain is tough. These calcium stains will in turn attract wine
sedimentation. The only way I was able to remove these stain patches was
with CLR (used to remove calcium deposits). Now when my carboys are not in
use I make sure that they are dried and sealed.

> wrote in message
oups.com...
> Do you have access to an air compressor and a spray nozzel? You could
> slip (such as) an engine spray nozzel down in there and with a little
> water jet them off.
>
> I wonder if spraying steam in from a carpet cleaner or a shark or
> whatever the little handheld steamer is called.
>