Water disenfectant question

[mabrungard]

@kramerog

Martin, are you referring to nitrogenous compounds being in the source water or added by the water supplier? Inquiring minds want to know.

Do you still recommend Campden even though the nitrite, nitrate and nitrite + nitrite results are non-detect?

Endogenous nitrogen compounds in the source water that can include urea or ammonia that are not detected by nitrite or nitrate testing.  This can be common in agricultural areas. Nitrate and nitrate are breakdown products in the Nitrogen cycle and they take time to develop.

[dmtaylor (Dave Taylor)]

@neuse

@dmtaylor

Just use Campden then don’t worry about it.  I keep a 5-gallon jug filled with Campdenated tap water at all times (and if I brewed bigger batches, I’d keep 10 or 15 gallons).  When it’s emptied, I fill it back up and add 1/2 crushed Campden tablet.  Cheap ‘n’ easy.  The reaction is said to be instantaneous, but I figure it’s easier to just have it all ready for next time.

I’m surprised that you can keep a jug of water permanently without having a problem with it. I once had a nasty bacteria build-up in my swamp cooler. (Now I add bleach every few days.) Apparently, keeping everything “brewing clean” makes the difference.  Does it stay pure enough to use on the cold side, without boiling?

As far as I know, it’s been fine.  I don’t live in the tropics where bacteria might thrive, I’m in the frozen state of Wisconsin, so that might help.  Anyway, it’s always boiled after the mash, so I wouldn’t really care anyway.

@denny

@Buckeye_Hydro

I see people using 10" x 2.5" carbon blocks fed by a garden hose, and it makes me cringe.

A 10" x 2.5" carbon block typically has a max flow of 1 gpm, so we typically recommend people go with half of that, or 0.5 gpm. 
Garden hose flow is typically about 5 gpm - 10x the desired.  When you push water through the carbon faster than it can be treated, you’ll have chlorine in the treated water.

I rarely see mention of flow rates through carbon in the brewing forums.

That last sentence makes an important point.

I agree.

[neuse]

@mabrungard

@kramerog

Martin, are you referring to nitrogenous compounds being in the source water or added by the water supplier? Inquiring minds want to know.

Do you still recommend Campden even though the nitrite, nitrate and nitrite + nitrite results are non-detect?

Endogenous nitrogen compounds in the source water that can include urea or ammonia that are not detected by nitrite or nitrate testing.  This can be common in agricultural areas. Nitrate and nitrate are breakdown products in the Nitrogen cycle and they take time to develop.

This made me curious about nitrogen compounds in RO water. I checked on this website: What Contaminants Can Home Master RO System Remove | The Perfect Water
It shows up to 80% removal of nitrates, so still some left in RO water. I didn’t see any mention of endogenous nitrogen compounds.

[majorvices]

@kramerog

I find that filling my hot liquor tank the night before brewing with the lid off and heating the water to mash in and sparge temperatures again with the lid off is enough to drive off chlorine. Boiling isn’t necessary. YMMV.

That works for chlorine but not for chloramines

[brewthru]

Try adding 0.5g potassium metabisulphite to 20 gallons of water in the HLT (if using less water, then scale).