So I would like to start using my tap water for my brews, but the water smells like a swimming pool out of the tap. So ive read about campden tablets and they are supposed to instantly get rid of chlorine and chloromines. anyone use them and have some advice on effectiveness? not totally ready to go pure r.o. water then build my profile accordingly yet. so I'm thinking to start, get rid of the two major issues with the water, and monitor ph in mashing. Then move onto more advanced techniques later.
Campden does work, as long as you use it before putting any malt in the water. The old advice said 1 tablet was good to treat 20 gallons of water. However, a few people have reported occasional problems in this amount so I personally use 1 tablet for 10 gallons now instead (or 1/2 tablet for 5 gallons). I haven't had a problem in years. Cheap and effective.
There's a John Palmer brew session out there on You Tube somewhere and he uses a campden tablet saying that 1 tablet treats up to 20 gallons. For my routine, I mash in with a few gallons and sparge with a few more gallons (depending on recipe) and I slice one tablet into two and use one half for my strike water and the other half for my sparge water. All my batches yield 5 gallons of beer. My tap water also smells like a swimming pool. My resulting beers have all been fine so far. I have never tested a batch using just plain old tap water though so I can't comment on campden effectiveness.
As another technique, you can also get your mash and sparge water ready the night before in buckets or whatever, as chlorine will evaporate off. Then use campden as well to ensure removal (as well as chlorimates or whatever it is) before use. I use 1/4-1/2 tablet per 5 gallon, with the water filtered thru carbon as well.
I started using tap water 2 years ago and have never looked back. Haven't noticed any difference flavor-wise when comparing to the gallon jugs of spring water I used to use. I've used as little as 1/4 tab for around 9 gallons of mash/sparge water and that seems to take care of the chloramines. Water chemistry can be as intense as you want to make it. Everybody's water is different but I've had good luck with mine by adjusting with 1 tsp CaCl, small amount of gypsum and treating with campden.
Not to hijack this thread or anything, but I have a campden tablet question that I've been curious about as well. Does anyone know if there is any harm in using too much campden? Typically I collect 8 gallons of water into a large jug the night before I brew, and I'll shave in roughly a third of a tablet to treat the chlorine. Even though it's not a full 20 gallons of water, is there any harm in just crushing a whole tablet into the water? They're dirt cheap, after all, and it's a bit of a pain in the arse to only use part of a tablet.
I don't use campden tablets, but according to the German Brewing Forum guide to low-oxygen brewing (PDF), a campden tablet contains 440 milligrams of sodium metabisulfite. Each milligram of sodium metabisulfite per liter will contribute 0.24 ppm sodium to the liquid. So if you are dosing 8 gallons (~30 liters), I think a tablet will contribute about 3.5 ppm sodium to your water. Obviously if you used a third of a tablet, you would get a third of that, so the difference between using a full tablet and 1/3 of a tablet is about 2.3 ppm of sodium. Similarly, sulfite reacts with oxygen to produce sulfate. Based on the numbers in the document I linked to, I think that the maximum amount of sulfate you would get from a campden tablet in 30 liters of water is about 11 ppm. Remember, that assumes that all of the sulfite is converted to sulfate—I don't know how realistic that assumption is. The difference that using a full tablet makes, compared to using 1/3 of a tablet, is about 7.4 ppm of sulfate. Speaking personally, I would not worry about the small amount of additional sodium and sulfate that would result from using an entire tablet. It's maybe something to keep in mind if you are trying to dial in a very particular level of sulfate, but I would not wager very much on anyone's ability to detect a difference that small in the taste of the beer. A separate question is what happens to the sulfite that is not converted to sulfate by reaction with oxygen, if any. I don't know the answer to that question. Based on the amount of sodium metabisulfite recommended by the German guide I linked to above (which is massively more than the amount you are proposing to use), I suspect any residual sulfite in your wort will not cause any problems. When using sodium metabisulfite at much higher levels, @OldSock reported "Finish has a hint of chemical-bitterness" and "the lingering flavor isn't one that calls out for another sip." He later described dumping the last gallon of that beer. But in that case he was using 15 tablets in 18 gallons of water, more than 6 times the proportion that you are contemplating using. When he brewed with half as much sodium metabisulfate (so still more than 3 times what you are thinking of using), he got a good result.
No harm, especially if you're boiling the wort. If adding immediately prior to fermentation like you would for (*gasp!*) cider or mead, then it harms the yeast. But before the boil, nah, no harm in it.
I fill my HLT up with 15 Gallons of water the day before brewday, and use 1 tablet per 5G. I have not had a problem in brewing traced back to camden usage. My tap water smells and tastes fine, as I have a filter-less softener, and UV light treatment system. But it still comes from really crappy source, hence campden
