campden tablet, is this right?

[HBHB]

Keep in mind that free gases is what you smell when the water's running. That's what is not in the water.

Here's a paper that discusses use of "Campden" to dechlorinate by sulphonation.

http://water.epa.gov/scitech/wastetech/upload/2002_06_28_mtb_dechlorination.pdf