My aunt was stopped at the entrance of the community last year by a young man.

He was wearing a white shirt, with a work badge on his chest, and handed her a glass of water.
He said, "Auntie, try this, it's water from your home faucet. I just fetched it upstairs."
My aunt took a sip, frowned.
The young man said, "You can tell, right? This water is a bit astringent, probably a layer of white scale from boiling in the pot."
My aunt said yes.
The young man said, "That's right. Your building's water pipes are aging, the rust taste is covered up by bleach, but the mineral content exceeds the standard. Drinking it long-term isn't good for your kidneys."
That day, my aunt bought a water purifier for over four thousand yuan.
After the young man left, she boiled a pot of water.
The bottom still had a layer of white scale, exactly the same as before.
She called and asked, and the other side said, "Just rinse it a few more days, it’ll be fine."
She rinsed it for three months, but the scale didn't budge.
My aunt accepted it, feeling like she had been taken advantage of silently.
Until last month, I went to her house and saw that the water purifier looked quite new.
I asked if it was good, and she told me the whole story.
I said, "This is simple."
Right in front of her, I called the tap water company.
The customer service after hearing the story said one sentence: "Your community just replaced the main pipeline last year, and the water quality testing reports are posted on the community bulletin board every month."
Then I called the water purifier manufacturer.
The manufacturer checked the serial number and said one sentence: "Your machine's filter cartridge only works against silt and rust, not scale."
The one that removes scale is a different model.
The water they gave you tastes good because they pre-filled the bottle with purified water.
My aunt stood at the kitchen door, holding the cup of water with white scale.
After a moment of silence, she said something I still can't forget:
"I've been drinking it for half a year, not because I was afraid the water was bad, but because I was afraid my kidneys really weren't good."
She dismantled the water purifier, threw the filter into the trash.
Then she asked me, "What should I drink now?"
I turned the tap to maximum and told her, "Drink directly.
Your water is cleaner than that young man's white shirt."