Reconditioned water TDS

Martin Fortin

Hello,
I was told that the best espresso extraction and taste are obtained with water having 150 ppm TDS. My water tap is actually at 30 ppm TDS. Is it advisable to add TDS with a reconditioning water system?
Could you give me insight for the following:
1) Can we really taste the difference in the cup from 30 PPM to 150 PPM?
2) What about Reiss recommandation of 80 PPM or less so as to avoid lime build-up? How can it be compatible??
Regards
Martin

Stephen Jenner

Unfortunately Martin, TDS is not a good indicator of water quality...

TDS means T(otal) D(issolved) S(olids), so what you see at 30ppm could (depending on where you live) be ultra clean water, with a little bit of temporary hardness (like chalk or magnesium thrown in), or could be free of temporary hardness, and loaded with cumulative toxins, like fluoride, the pill, nitrites, nitrates, and all that good stuff. They are pretty accurate, but they are not able to tell the difference between one particle and another.

What I have done, and this is documented elsewhere on this site, is to clean my water completely, using a "reverse osmosis" system, and then added my desired amount of temporary hardness, in the form of a cartridge loaded with 50% magnesium and 50% chalk (calcium)...

So I know that I have clean water, and that my TDS reading is all from this cartridge.

I don't want to put words into Reiss's mouth (v. dangerous )... But I am pretty sure that he will suggest that you find out how much of that 30ppm is the desirable temporary hardness. If you have something near 30ppm, you are just about OK, as far as taste, whilst the amount of hardness is enough to protect your boiler, without ruining it. You do this with a test kit, that tests for a particular type of suspension... i.e. chalk. There are kits for just about everything, so total water analysis would get really expensive.

The aim is to get up near 70-90ppm of temporary hardness, but a little less will not do any damage. London water is actually quite clean, they don't add fluoride and because of the high population they perform extra processes to get rid of some of the toxins... The problem with London water is that chalk adds something in the region of 350ppm to the water, and this is a boiler/group killer.

Reiss Gunson

hi martin

apologies for not replying sooner

stephen has covered it all really - total temporary hardness is a subset of the total dissolved solids value

I'm sure the good people at the SCAE/SCAA are right, but do you want to spend $1000 on engineering your water?

bear in mind it isn't just the initial capital outlay - all this fluff has to be maintained and serviced, yearly at least

if you suffer from total temporary hardness above about 80ppm (mg/L) then you have to take action

if your total temporary hardness is too low you may also have to take action as the level sensor in your boiler will become unreliable at low levels of total temporary hardness, i.e. anything much less than 30mg/L, but you have had your L1 for some time so presumably you aren't incurring that issue, so leave well alone would be my advice

it is true that lifting up the magnesium carbonate value is meant to give a better tasting espresso, cf calcium carbonate, which is why stephen did the 50/50 mix in his calcite filter rather than just 100% calcium carbonate

kind regards


reiss