Efflorescence 

Efflorescence is the formation of crusty, white salt deposits, leached from mortar or masonry as water passes through it.

The efflorescence was a clear sign that my foundation had water.

Efflorescence by Paul Thornton November 29, 2007

Effluvescence

An emanation of bubble (ie. evil bubbles).

Derived from the words effluvium and effervescence.

When drinking boiling acid, take care to hold your nose thereby avoiding the inhalation of a terrible effluvescensce.

Effluvescence by Apt Soodo-Nim November 14, 2004