Question for RO Users

How do you determine when to replace your RO filters?

I’ve had my RO for a couple of years now. I don’t go through a whole lot of RO. I run 1 or 2 plants at a time and use RO for cooking, drinking water, and coffee. I noticed a few days ago that my RO has a foul taste, even though PPM remains under 100. I replaced the filters yesterday and am flushing the system now. We’ll see how it tastes later today.

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I just got a RO buddy a few weeks ago, on my filter it says 6 month or 1500 gallons to change filter. not sure if thats a marking thing or what. no way i can tell how much water i used but ill test mine when it hits six months. let me know how it tastes after the flush

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I don’t use RO instead I use the ZERO water filter…I would think you measure the PPM output of the RO system and replace filters when that starts to go up

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I’ve been using the R/O Buddy for several years now. I change the filters every 6 months, and the membrane once a year on average. That’s under pretty heavy use. I go through about 10 to 15 five gallon jugs a week. When the filters and membrane are new, the TDS readings are very close to zero, sometimes 2 or 3 ppm. After a few months the ppm of the water starts to go up a tiny bit at a time. When it reaches about 25ppm, usually 6 months or so, I replace the filters. Then the membrane gets replaced either in another 6 months, or if the ppm gets too high for my liking. I try to stretch as far as I can cause everything is so expensive now. If I’m near the end of a grow I wouldn’t be in a hurry to replace it because the ppm is up to 50, but if I had younger plants I’d rather start with the lowest ppm possible, so I’d replace it early.

If you buy the replacements on Amazon, make sure you have a roll of Teflon tape on hand. The filters don’t come with the little fittings on the ends. You have to take them off the old filters and reuse them.

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Agree with my fellow Rush fan. :slight_smile:

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Happy I replaced the cartridges. The RO water tastes fine now. Actually it had no taste, which is what I was looking for.

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Usually depends on what RO system you have, the more expensive ones you change every year and some every 4-6 months, depending on which one you got

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I agree the manufacturer suggested replacement is 6 months or 1500 gallons. But also wouldn’t hurt to also check the ppm when after each replacement. Even though for plants under a 100 is ok . My ro runs 10ppm . I always write the date on it and every six months it gets changed regardless. I don’t use no where close to 1500 gallons. But if using for drinking and cooking and taste isn’t right definitely change it out .

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I just changed my sediment filter after about a year of fairly heavy use. It’s a cheapo RO buddy. I noticed it was getting quite slow. The ppms were still low but it was taking about 15min/gallon vs 10min with a new filter. I find that warmer water goes faster so I shoot for around 75*

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Every 6 months here. We use ours a lot and our well water is brutal so I dont let mine go to long. The 6 month mark has worked well so far for keeping the taste nice and PPM where they need to be. Rarely see mine get over 55ppm and thats with tap at almost 800ppm.

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PPM measurements under 100 are not always reliable, but the PPM before the change was 70 and after the change it reduced to 12.

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