Britafilter

September 30, 2007 6:35 AM

Here's another question about Brita Water Filters. Presumably the efficiciency of the cartridges is affected by the amount of water they filter as well as the length of time they are in place? In which case, how many litres would one cartridge safely cope with? And is there really a maximum time required before changing it?
posted by ikp to Food & Drink (10 answers total)

In my own experience the water quality will slowly deteriorate over the life span of the cartridge. However, I didn't notice much difference in mine and I just changed it for the first time in 8+ months.

I have noticed that as the filter gets older the water filters through more slowly. I would assume if the filter isn't completely clogged that the water is still getting partially filtered. That's just a guess though.
posted by aetg at 6:53 AM on September 30, 2007

The instructions on American pitcher cartridges say 'change after every 40 gallons filtered', which translates to 150 litres or thereabouts. I've not noticed a substantial difference beyond that, though you have to assume that the absorption properties of the activated charcoal are saturated after a certain point.
posted by holgate at 7:07 AM on September 30, 2007

We go through 2 pitchers a day and a distinct taste begins to appear after (+/-) 2 months.
posted by bru at 7:24 AM on September 30, 2007

I'd've thought the amount of water would be far more important than the amount of time.
posted by pompomtom at 7:29 AM on September 30, 2007

My friend's family doctor told her that, if you're a single person, you should change the filter every month. He said that the water doesn't get used enough when you're single or even a couple. This is anecdotal, but still worth considering, I think.
posted by acoutu at 8:19 AM on September 30, 2007

It's not just charcol; there's also an ion exchange resin. Once this is saturated the filter isn't doing its thing anymore.
posted by ikkyu2 at 9:27 AM on September 30, 2007

My Breville water filter (which uses Brita Maxtra filters) has a little electronic countdown bar which you reset every time you change the filter - it looks like a little LCD based progress bar. The countdown lasts exactly 4 weeks; they recommend you change the filter once a month.

My water filter/cooler is quite big compared to other kitchen ones (i.e. not just a 2pint jug) and is aimed more at families so I'd assume that with regular (8 glasses a day, per person) use this thing should last the average 4 person family a month.

My girlfriend and I change it monthly anyway, just to make sure we get the best quality out of it. We've never had any issues with the quality deteriorating.
posted by TheAspiringCatapult at 10:11 AM on September 30, 2007

On the other hand, we change our filter cartridge maybe once a year. This is far less often than we're supposed to. But there's nothing wrong with the water going into the pitcher— the tap water here is pretty nice. We only have the filter to improve the flavor a bit by removing chlorine. So we change it when we taste the difference, which turns out to be pretty infrequently.
posted by hattifattener at 1:21 PM on September 30, 2007

Well, since no one has thrown around the 3 month mark, let me be the first. I thought you were supposed to change it every three months. And I thought I read that on the filter wrapper (but don't have one to look at at the moment.

And, while time may not be as accurate as the amount of water you filter, it's easier to remember. Does anyone here "tick" off the number of liters/quarts they filter? Not me.
posted by Taken Outtacontext at 11:54 AM on October 1, 2007

On the other hand, we change our filter cartridge maybe once a year. This is far less often than we're supposed to. But there's nothing wrong with the water going into the pitcher— the tap water here is pretty nice. We only have the filter to improve the flavor a bit by removing chlorine. So we change it when we taste the difference, which turns out to be pretty infrequently.

If it's chlorine and not chloramine, the act of putting it in a jug in the fridge for a day or 2 is enough to get rid of the chlorine in it. This is how people with aquariums treat their water prior to adding it to the tank.
posted by garlic at 8:58 AM on October 2, 2007