water softener + water filter

I have a softener and filter.

The softened water goes through the water system in the house, and is available at each tap (kitchen, bathroom, shower) and the attic tank

The water filter isn't connected to the softener. It takes in unsoftened mains water and is available via a second tap at my kitchen sink only.

So my connection is your second option - drinking water is hard water which is filtered. The filter system I have does remove a lot of the limescale by filtration rather than salt.

Why is that?

Doesn't that mean you will still get limescale in your kettle as will be filling it from mains?

Regarding the danger of sodium I looked into it a bit more and it seems somewhat dependent on how hard your water is.

If it is only a bit hard it shouldn't be too much of a worry for most.

Still best to avoid for infants and those with issues.

The reason for water filter is mostly for taste afaik, remove the chlorine and the water tastes better.

So the answer does not have to be black and white here and I'll address why to all the questions raised, so no absolutes here or any 'no no's as such.

Salt is sodium chloride, (40% sodium 60% chloride) and only sodium exists in softened water at a very minuscule trace level 0.001% typically similar to supermarket bottled water, although bottled waters do actually have chloride and therefore salt, but to a very safe and marginal degree for most.

Even supermarket bottled waters can exceed the sodium level recommended for infants and sometimes more than softened waters. For infants 0-1 years old it is recommended to use the W.H.O. suggestion of 1/6th the safe adult level for potable or tap water sodium of 33 mg/L based on the 200 mg/L used for adults as per EU Drinking Water Directives and Irish EPA and HSE and so on.

So the big question ? Can you provide softened water to the whole house, every tap, and is it safe ? A little extra knowledge can be wise thing, so the answer is Yes of course, but think about some small issues ...

1) Softened water sodium depends on incoming hardness and is as a rule of thumb 40% of the hardness value. So very hard water at 300 ppm / mg/L has 120 ppm or mg/L of sodium when softened (40%). Now adults can avail of up to 200 ppm or mg/L of sodium in safe legal potable tap water by all national and international potable water safe limits.

2) But for infants between 0-1, for that time when they are very young you might want to consider a safe filtration technology like RO (reverse osmosis) or some brands of bottled water like Volvic (20 mg/L sodium) usually spring waters containing very little salts or as they are known "Minerals". RO is able to create the best quality of water, even allows for minerals at the desired levels, all boxes ticked.

3) So when addressing the idea that salts are indeed minerals, it is a case of how much and what type ? Salt or Sodium Chloride is of course one of the main essential minerals our body needs, but like all things there is the "Goldie Locks" principle of not too much, not too little, but just the right amount. Diet sorts that out, food has all the minerals we need, but for tap water we can adjust the all mineral / salt values as to how we want them.

So hard water comes in to the house, do you want to ...

i) leave it all hard ?

ii) soften all the house, all taps ?

iii) soften the domestic water in all the house but leave the cold kitchen tap hard ?

iv) soften all the domestic water in the house and fit a separate hard fed carbon filter tap ?

v) soften all the water in the entire house and fit a separate soft fed carbon filter tap ?

vi) soften all the water in the entire house and fit a separate hard fed RO filter tap ?

vii) soften all the water in the entire house and fit a separate soft fed RO filter tap ?

viii) fit a tri-flow or three way tap option (discuss later)

Not "Black and White" is it, but easy answers, once you know how. So the answer is informed selective choices, with good information to make a solid informed choice of what you need or what you prefer or both. So look again below ...

i) certainly not hard to all taps, the whole house will be wrecked, especially in Galway County, you will know yourself.

ii) yes, great choice soften the whole house, all fine but are you at that 0-1 year age toddler stage, need Volvic for a year, or get RO water ?

iii) soften all water but not the cold kitchen tap, well ... not really the best choice, but up to you, wrecked kettle and bad tea and coffee !

iv) soften all the water and fit a hard fed carbon filter tap, better choice now, and you could fill the kettle from the soft kitchen tap.

v) soften all the water and fit a separate soft fed carbon filter tap, not a regular choice but can be done. Filter out chlorine at least.

vi) soften all the water and fit a separate hard fed RO filter tap, the RO will get killed by hard water faster, but the mineral balance is good*.

vii) soften all the water and fit a separate soft fed RO filter tap, excellent choice, the best of all. All boxes ticked*.

viii) Tri-flow taps or three-way taps allow for hot, cold and filtered all on the one mono-bloc single 38mm hole bore tap. (Not boiling tap).

* 1 in 100 water users might have ultra sensitive test profile and want to taste all the options of water how the various filtering techniques allow, and could find RO the best after all, minerals optimised with option vi) but nowadays mineral cartridges are available for those very few who want it.

So, any choice really, but i) is bad, not recommended, but all up to the house owner. If water is softened in certain areas (Dublin and East also Kerry, Cork etc) and depending on your diet you may find drinking softened water occasionally has so significant impact on renal or blood pressure implications and what the doctors or blood tests show, as softened water sodium is at an extremely low trace level, generally 100ppm average nationally, 60ppm to 140ppm say. RO sorts it out, and yes you can have all the minerals with current RO systems, not what some old plumbed RO units or RO DI units had as a question back in the day, even then food always provided all your minerals, all you could ever want.