ZeroWater: let’s get this clear

Here’s something a little bit different— not beer, cider or spirits but water.

It’s easy to take for granted if you live somewhere with decent tap water. It’s just… there. In your house. Whenever you want it. So when I was contacted by water filter company ZeroWater asking if I wanted to review their filter jug, my initial reaction was “uh… why?”

But I was intrigued when I saw this video.

I had been watching other videos around the time about making clear ice. (For cocktails, in case you were wondering. It’s just… nicer.) You can do it at home, but it looks like quite a faff. Apparently much of the cloudiness in the ice you make at home is down to impurities in the water.

It got me wondering… would water from a ZeroWater filter make clearer ice?

And I had a few other questions, namely:

• does the water taste better after it’s filtered?
• does it make a noticeable difference to tea and coffee?
• what would happen if I put some beer through it for shits and giggles?

The Jug

OK first things first: the jug itself. ZeroWater sent me a free sample of their 12 cup jug, which can hold 2.8 litres of water. I’m not a fan of how typical water filter jugs look, but this one is no worse than any of the others out there.

This just from ZeroWater has a tap built into the handle. You push in a button and water comes out from the bottom of the handle. I say comes out… dribbles might be a more accurate way of putting it. It would take a long time to fill a glass this way. And you’d either have to pick up the jug — in which case why not just pour? — or have it sitting half-on-half-off a flat surface somewhere. Honestly, I don’t see the point of this feature. Perhaps I’m missing something here?

This just doesn’t fit in my fridge. Well… it might, but I’m not willing to sacrifice the space or bother rearranging the internal shelves. And my fridge is not small. Perhaps if you have a giant fridge this might work. I feel like if you’re a filtered-water sort of person you might also want it chilled, so that’s something to consider.

The top reservoir is large but not huge, so the jug doesn’t feel too top-heavy after you’ve just filled it from the tap. It took about 8 minutes for the water in the top to filter all the way, which left the main part of the jug about one-third full.

Filtering: how does ZeroWater perform?

OK, the next big question is does ZeroWater keep its promises about filtering the water?

ZeroWater’s whole deal is that it leaves your water with nothing in it other than water. It even comes with a little stick for measuring TDS, which stands for total dissolved solids. It doesn’t indicate what solids. So all you know is that there is either… stuff… in your water or there isn’t.

Before filtering I measured my London tap water at 296 ppm. After filtering it was indeed 000 ppm.

OK. Yeah. Still… what is it taking out? In her message the PR mentioned some ‘alarming’ news:

A recent survey by Zerowater UK revealed that 70% of Brits are still drinking unfiltered tap water. Unfiltered tap water contains microplastics, but bottled water contains twice as much plastic.

Sounds nasty, doesn’t it? I wanted to know, how much bad stuff is really in my water to begin with? And might this filter also remove things that are good from your water too?

Just to be clear on this matter: my tap water is perfectly safe. My supplier, Thames Water, publish information about water quality on their website. Here’s what it says for my area:

Moreover, like most of us, I have functioning kidneys which can cope with tap water just fine.

And while 296 ppm might sound high it’s really not. That ‘ppm’ stands for parts per million. So 296 ppm equates to 0.0003 parts of whatever. Looks a lot less significant when you put it like that, doesn’t it?

Still… the filtered water might be kinder on my kettle.

Does ZeroWater make a difference to tea and coffee?

I tried making tea with the filtered water, and it certainly looked brighter in the cup. But unfortunately that’s about as far as it went. Other than that I found no discernible difference. The same went for coffee…

Perhaps if you’re a huge tea or coffee nerd you might notice it more. Maybe if you drink whole leaf tea with no milk or sugar it might be more evident.

For me though, I could find no benefit from using the filtered water.

(Again, long-term it might be kinder for my kettle. But whether that works out more economical than buying some descaler every now and then… I’m not so sure!)

ZeroWater taste test

It was… fine. Water from the ZeroWater filter certainly tastes softer than my tap water usually does. But beyond that… come on… it’s still just water.

Does ZeroWater make better ice?

Does it make clearer cubes? Yes.
Does it make clear ice cubes? No.

I made some out-size ice cubes using tap water and water from the ZeroWater filter. The filtered cubes were definitely clearer, but they’re not completely clear. The filtered cubes did freeze in a rather beautiful pattern that looks like an icy firework frozen in time.

So yeah, that was nice. I prefer the filtered ice cubes, but probably not enough to justify the cost of buying replacement filters for the jug.

ZeroWater running costs

So how much does a ZeroWater jug like this cost over time? Herewith, some quick maths.

First up, here are the costs for replacement filters using prices taken from ZeroWater’s website.

And here are ZeroWater’s estimates of how long each filter will last (in litres) based on the TDS levels of your tap water.

From which we can work out the cost per litre:

As you can see the cost per litre varies quite a bit depending on your water quality and whether you buy filters in bulk. But for me it would work out somewhere between 36p and 20p per litre. That’s quite a lot of money for some rather dubious benefits. But enough nerding out. Time for some fun.

Filtering beer for a laugh

Time at last for what I’m calling the Schofe Test. I chose a bottle of dark-ish beer than had been hanging around a little while — I’d characterise it as a nut brown ale with a tawny tinge — and poured it into the top.

Almost immediately it started coming out clear at the bottom of the filter. Amazing!

But then some faint colour started to appear… I suspect the clear stuff was just water than had been sitting in the internal part of the filter being pushed through by the beer above.

The next thing to do was get the TDS meter out and see what effect the filter was having on those measurements.

The beer was significantly slower than the water to pass through the filter. It took around 30 minutes to get through 500ml.

When it was done, the liquid — honestly I couldn’t say if it was beer or water at this point — was certainly much lighter in colour than when it started, and it was totally clear too. (Clear as in ‘not cloudy’, which is not the same as colourless.) It had the texture of softened water but kept a slight hint of barely flavour to it that I found more reminiscent of whiskey than of beer, which was interesting. But it wasn’t great.

Also, anything that’s been through the jug since has kept that slight flavour, so I guess that filter’s shot now. Ah well.

ZeroWater, my conclusions

My tap water tastes fine and is perfectly safe to drink so ZeroWater has no benefit for me. If you live somewhere with nasty tap water then maybe a filter is worthwhile. In that case, you’ll need to decide whether this ZeroWater filter is better than others, e.g. Britta. I haven’t done a side-by-side review so I can’t answer that for you.

The filter certainly removes pretty much everything from the water you put through it, which means ZeroWater does live up to its claims here. But whether that matters, again, is up to you. Personally I can live with drinking the 0.00025 parts Calcium Carbonate plus 0.00005 parts whatever per 1 part water that comes out of my tap.