Treating water with campden

So, I've noticed that recently, my tap water is tasting like there's a bit more chlorine in it. So for my next brew (likely an extract batch) I want to try using campden tablets to remove chlorine and chloramines.

I've read posts that say campden will help me remove the unwanted substances from my water, but at what point am I supposed to add the campden tablet? And is there anything more I need to know other than just throwing it in a brewing like normal? IE does it have to sit around for a while?...

Thanks!

I read in brewing classic styles to crush it and add it to the water before boiling.

Have your Beers tasted bad without the Camden tablets?

My local tap water tastes fine, but every batch of beer I've brewed with it has tasted terrible. I used Spring water with good results, but I'm cheap. SO, I finally made another test batch with my tap water and camden tablets. I didn't read the instructions and added a whole tablet to five gallons of water. It's only supposed to be 1/4 tablet per 5 gallons. I tasted it last night and nearly all of the nasty taste that was in previous beers is gone. But, since I over did it, there is a bit of a sulfite/sulfate flavor to the beer. But not enough to discourage me from drinking it.

I've used 3 other city water sources with no problems. Only mine seems to not like being turned into beer.

Suggested directions say crush 1/4 tablet into 5 gallons and let dissolve and you're good. So, about 5 minutes before you use the water should be plenty of time.

BCS also says that it only calls for 1/4 of a tablet, but pitching the whole thing wouldn't hurt anything. That's what I do and I haven't noticed any off flavors.

Thanks for the great replies.

I havent brewed since I noticed the "extra" chlorine in the water, and beers prior to that havent been bad, I just want to know how to treat it "just in case".

Thanks again.

Yeah i think a 1/4 tablet will dechlorinate 5 gallons of water. YOu can just add a whole one, crushed, and the boil will drive off any residual sulfite (not that its harmful).

When I do this, I have a couple 5 gallon non PET water bottles, so I'll fill them and add the campden, then brew the next day. I believe once dissolved the campden should work within 5 minutes. I just use this method of overnight because its convenient.