What is this actually showing and how do you use it?
Eric wrote: barneey wrote:
& for the same amount of money you could get your water tested once a month for a year to build a water profile
useful if you water bounces around a lot, mine doesn't really change at all so am fairly confident the figures can be used brew to brew. Always check Alkalinity & you could check TDS also before each brew.
My water varies greatly as can be seen, but as you advise, here is a graph of TDS/cations from measurements by WallyBrew.
There's another for TDS/anions.
A lot easier and quicker to use and a lot cheaper.
Edited to restabish original graph and add a second.
Pure water is very rare as it dissolves parts of many elements and compounds it contacts and so can vary substantially from place to place and also frequently with time.
A beer can be made using unaltered water from any UK regulated supplier while treatment can substantially change the finished product, but unless it is know what the water initially contained, any conclusions drawn might be wrong and lead to wasted effort and poorer results. Water company reports are historical and not always suitable for our purposes. Apart from measuring alkalinity, general hardness and TDS, testing is complicated and requires expensive equipment and so, in my opinion, it is worth having it done by a professional.
A downside to this is that when your water varies, and many do, your data can be misleading, so to deal with this you might have a series of tests done and choose the most appropriate on the day you brew. A Salifert Alkalinity kit does a test in a few minutes for less than 10 pence, a general hardness test much the same although I find I don't need to do this. A TDS meter can be bought for about £5 and should last a few years and the test takes a few seconds.
As these dissolved materials can influence the brewing processes it is advisable to know what they are and in what quantity before attempting serious water treatment.
The graphs plots measured concentrations of the major cations and anions that influence brewing processes against the measured Total Dissolved Solids.
Jocky wrote:It looks to me like it's the proportion of each of the cations/anions as part of TDS? And does this assume that your water source does not change, so the ratios of your ions stay roughly the same and only the TDS changes?
Wallybrew analysed my water several times during 2014 when there was substantial variation in its mineral content. I then plotted the graphs to show there was reasonable correlation between TDS and major ion concentration by their proximity to a straight line. Accordingly I can take an alkalinity reading to adjust the alkalinity with acid and a TDS reading on the day I brew to be reasonably confident of the magnitude of major ion concentration and what amount of salt additions might be needed.
Without patience, life becomes difficult and the sooner it's finished, the better.