ZeroWater

They tell you if you mail your old filters back to them, they will recycle them and give you a coupon for $20 towards your next purchase. So I mailed them to Zerowater ($10 my expense) shipping, waited a month for the coupon code (which I never received). Emailed them and they finally sent one that does not work on their website. The reps say that no codes are working at this time... I've been trying to buy filters from them for three months. We all get pretty busy in life, no one needs to check back over a dozen times to make a purchase. Vote with your money and support green companies with integrity instead.

Our southern Arizona water is undrinkable without filtration, and these do nicely, When they offer specials and you buy in quantity, the cost comes down to about $14.00 per filter, and one can last 30-45 days, depending on usage. Unfortunately, the company doesn't seem to offer specials any longer. (I thought they'd gone out of business.) But now that I'm down to my last filter, I think I'll look elsewhere for a water filter solution. Last year, they had a security breach and didn't really handle it well, in my opinion. (I was notified BY MAIL even though I order online. The notice that my card could be compromised arrived on a Saturday. Nice.)

I bought stuff directly from its company (not Amazon). Slow and rude email responses, and what a diminishingly rude tone of speech over the call. It was super unprofessional. I'd probably get better service from McDonald's.
Avoid this company and install an RO filter. Or buy stuff and make sure you won't interact with them. So sad to see how this type of business can run like this. Maybe this business isn't serving great products after all. You can tell what's the inside look like from what the outside looks like (aka CS). It's all rotten, like fungi. And I got no business dealing with a fungi-like company, especially when it's supposed to serve clean water.

I bought a zero water pitcher and after using it twice the water tasted like vinegar and kept getting worse. I went to buy new filters and they're double the price of Brita and Pur. I called the company to complain about the filter and after the call I kept getting a lot of"spam" calls and I'm still getting them, I think they gave out my number

I was given a new Zero Water dispenser. There is a button to press to dispense the water. The button has to be pressed for the duration of water dispensing, and it is hard to hold. The filters are ridiculously expensive and don't even last that long. The water doesn't taste as good as it should. After about 3 months, the water wouldn't drain out of the reservoir into the dispenser at all. I'd had enough, threw it out, and replaced it with old faithful.

We moved into an apartment complex that had bad tasting water. I saw the commercial on TV, so I thought "here is my answer!" So in August 2019, we purchased the 4.6 Cup Zero Water Pitcher that came with a water quality meter and one filter.

Out of the box, the meter didn't work; it registered 334 on the water. The water tasted better, so I didn't worry about the meter. Over the next 11 months, we purchased 10 additional filters. Sometimes the water was better, and sometimes the water tasted so terrible that I discarded the filter and used a new one.

Contemporaneously, we had a problem with instant coffee and hot tea. When we added milk to our hot drink, it appeared like the milk curdled, and the drink would get thick. It was like we had added a thickener. We tried all sorts of things to figure out what the problem was. Never once did we even consider it might be our filtered water.

In October 2020, I put in a new Zero filter, but it had a metallic smell right out of the box. So that morning I used regular tap water. The milk didn't curdle. The light went on in my brain. It was the chemicals in the Zero filter. I tried making one more cup of instant coffee with the stinky filtered water; the milk curdled. I made a second cup with tap water; the milk did not curdle.

So my evaluation is P U.