# London water and what to do with it



## rws (May 7, 2014)

I'm looking for advice on water treatment - I know the subject has been done to death, but I also know that there must be several forum members who have very similar circumstances and I'm interested in what has worked well for you.

I'm about to have a kitchen extension done and would like to stop using bottled water to feed my machine. I have a Classic now, but of course with a bigger kitchen comes space for a bigger machine, so I will upgrade and am thinking of going with something plumbed in. London water being what is is, that will of course involve some sort of treatment to reduce the hardness - 278ppm according to Thames Water. I have a cheap TDS meter which read quite a bit higher (360ppm) but I reckon their results are more reliable. Taste is clearly just as important so I'll want to reduce the chlorine level in the water too.

I will also have an instant boiling water tap, which again needs protection from scale, so it would make sense to have one system to feed both that and the coffee machine.

I'm considering:

A small Reverse Osmosis unit with reminerlization filter, maybe from Osmio

BWT Bestmax Premium

Or even this, which I know little about, but seems an expensive option https://www.uk-water-filters.co.uk/Whole_of_House_with_Scale_Reduction.html

I like the simplicity of the Bestmax, but not sure that's a reason to choose it.

So do any of my fellow London coffee drinkers have any recommendations? What has worked for you?


----------



## Jony (Sep 8, 2017)

From what have read, I think a few use the BWT on here, plus what are you using it with?


----------



## ajohn (Sep 23, 2017)

I haven't seen one option mentioned in relation to coffee. Water softening has become more popular in manufacturing plants.. They generally use a salt based one. These contain a resin that does the business and is revitalised with salt. The resin lasts a long time. I have worked in a place where every drop entering the building went through one. My understanding is that it converts calcium carbonate to sodium carbonate which is soluble. Calcium carbonate is too within limits - it's the temporary hardness that causes problems.







I asked Severn Trent what their numbers represented and didn't get an answer even though the lady took my phone number so that some tech could phone back. The figure could be total hardness. It's pretty low around here.

A few people on here use an RO unit and then reharden it but I'm not sure what with. I have used one of these at home for other reasons and also in this case rehardened with calcium. Flow rates are pretty slow but increase with price and go down according to the degree of purification so are more suitable for producing stored water. Stored water doesn't want to be left sitting around for too long for obvious reasons.

I'd assume typical coffee machine purification is sized to suit the machine, flow rates wont be that high even on large ones. A hot water tap is a different animal. I wondered about one and decided to go for a hot water dispenser that can heat anything from a cup full to 1 3/4 L. It tells me when to descale probably assuming I live in a hard water area.

Some machines come with resin based filtration and the makers imply that there is no need to descale but suggest rather frequent filter changes that probably don't relate to the water capacity the filter makers reckon they can handle. They usually fit in the machines tank. These can be bought at reasonable cost and can be fitted to the end of a pipe eg

https://www.espressounderground.co.uk/Bestcup_s/3004.htm

The same site also sells salt based softeners - not noticed that before so may be a new addition. *Edit *Just add that I think these are about with better tap arrangements to aid revitalising the resin and flushing.

John

-


----------



## SurbitonBoy (Jan 26, 2018)

I end up using Distilled water with Third Wave Water salts to remineralise for pour overs and BWT Bestmax Premium for everything else.

I find I prefer the Third Wave Water flavour balance rather than the BWT which has a higher extraction rate, which make the BWT better for immersion brewing.

With the XL size and the water in Surbiton it lasted a year which is the longest they recommend without replacement.

If you order the Bestmax Filters from Europe they end up a lot cheaper than in the UK as the supply levels are terrible here, I got my most recent replacement from CoffeeDesk.

I wouldn't recommend a salt based water softener, as the Sodium levels will be much higher than recommended for coffee brewing.


----------



## Stanic (Dec 12, 2015)

What setting do you have on the BWT head?


----------



## SurbitonBoy (Jan 26, 2018)

Stanic said:


> What setting do you have on the BWT head?


It's on 3, the water test put it at 2 for steam generation but I find as the water sits in it 2 is too acidic when I make carbonated water through my Sodastream.


----------



## Scotford (Apr 24, 2014)

I'd look at an inline filter along the lines of a BWT, size depending on amount of use.

I have my espresso machine, batch brewer and a water boiler at the shop that CAN all run from the same filter comfortably with zero scale. I do use extra treatment on the outlets to both the brewer and machine but that's because I like to have a different water makeup for coffee over plain old boiling water. And I'm a massive geek. Point I'm making is that an all in one filter should do you very well for a wide range of applications.


----------



## Stanic (Dec 12, 2015)

maybe a RO system to remove scale and then a small BWT Mg2 filter with head set at 3 to return some minerals, would combat even the hardest water with relatively low investment in the long run


----------



## ajohn (Sep 23, 2017)

SurbitonBoy said:


> I end up using Distilled water with Third Wave Water salts to remineralise for pour overs and BWT Bestmax Premium for everything else.
> 
> I find I prefer the Third Wave Water flavour balance rather than the BWT which has a higher extraction rate, which make the BWT better for immersion brewing.
> 
> ...


Rumour has it that a lot of the resin filters use the same resin as the ones that can be revitalised with salt. Main difference is that it can't be done without dismantling the filter and doing it manually and then putting it back in. Seems some do this and as they are Ion Exchange resins that actually makes some sense. They remove one thing and replace it with another which is a little different to actually removing it. True de ionised water is best avoided. It will dissolve all sorts often to very low levels and they can be toxic - I've actually been warned not to be tempted to use it to make my coffee - instant at the time - at work. Good reasons too.

I'm inclined to believe that all that are sold for water softening will introduce sodium and remove calcium. The other thing that may be exchange is potassium but that's more associated with putrefying - removing certain metals etc.

Activated carbon is also included in some set ups as that can remove things that can't easily be removed by ion exchange.

John

-


----------



## SurbitonBoy (Jan 26, 2018)

The BWT Bestmax is a strong acid softener, so the Calicum Carbonate (chalk) is converted into Calicum Chloride and Carbon Dioxide, so no sodium added. So the balance of permanent to temporary hardness can be changed by adjusting the mix ratio on the filterhead before it goes through the final activated carbon filter.

My RO unit gets down to 30ppm which would be too low for making coffee. Maybe mixing RO and BWT water together to reduce the total hardness but I found measuring the minerals with a water testing kit to be too much of a pain, especially as the BWT waterhaving free carbonic acid in it until its boiled or heated.


----------



## Dylan (Dec 5, 2011)

Xiaomi do a compact smart RO and remin system... Not sure if it offers much over other systems of its type but worth looking in to as they seem to make good products. They also do a dead cheap electronic ppm testing stick, no idea of the accuracy.


----------



## ajohn (Sep 23, 2017)

Pass but if I look on BWT's site the section through their filters look much like any one else's that does the job properly - particle, carbon, ion exchange resin, more carbon and more particle. I also understand that the usual ion exchange resin will take up mg

Maybe I am looking at the wrong cartridge. Calcium Chloride is highly soluble in water and sometimes used in aquariums to provide a source of calcium.







My chemistry is no where good enough to wonder what ion exchange would be needed to finish up with it. Being curious and also having an interest in this area at times that might lead to many hours on the web - I'll try and resist though.

Some salt regeneration ones allow mixing of untreated water as well. I'd guess that the source of these I mentioned would rather sell units where various bits and pieces need to be added. The price of one of the tank filters they sell is pretty disgusting compared with what some one in europe might sell them for - if they could sell to the uk. The one I found wouldn't.

John

-


----------



## rws (May 7, 2014)

Jony said:


> From what have read, I think a few use the BWT on here, plus what are you using it with?


I currently have a Classic and will keep it for a short while but plan to upgrade to a dual boiler machine, which I will plumb in. That and the hot water tap in the kitchen will consume the water from the system. Don't know which DB machine yet, as I'll be looking for a second hand bargain


----------



## JamJames (Oct 14, 2019)

A whole house water soft system is recommended. This is convenient. You don't need to worry about the water quality problem in any place. It can extend the life of the water pipe in the whole house and remove excess components such as chlorine, calcium and iron.


----------

