The Brita water filter, how do you know when to change it?

the digital thing doesn't seem to do anything, nor does the manual dial, is one supposed to turn the dial every time they fill it? and if so, what about the digital thing?The Brita water filter, how do you know when to change it?When the flow slows, change it.The Brita water filter, how do you know when to change it?On my Brita water filter, the digital pad on the handle jug will start flashing on the fourth bar when it needs changing. And when you put a new one in, you are supposed to hold down the button on the pad till the bars all reach the top, then just let go and it's done.The Brita water filter, how do you know when to change it?I owned a Brita filter years ago. It came with a decal that you had to stick on the pitcher and that said the date you first used it and when you should buy a new filter.