Good Grains Gone Bad

Has Your Water Kefir Gone Bad?

Sometimes kefir grains go bad. They can become slimy, or the water kefir becomes thick and syrupy, the grains develop a white film, or they start to smell bad. Don't throw out your grains just yet! You can often bring them back to health again with a little trouble shooting and some TLC.

First, no matter what the problem may be, you need to check all the ingredients you are using.

  • Is your water fresh with no added chemicals? (no added chlorine or flouride)- SolutionUse bottled water, or boil water for 10 minutes and then let cool before using to remove chlorine. Fluoride can not be removed this way. You need to use bottled water if your municipality adds fluoride. Even bottled water that is labeled "spring water" can have bad additives like chlorine, sulphites, and other unwanted ingredients. Read labels!
  • Are your ingredients free of preservatives?- SolutionThe one that often seems to get by unnoticed is sulphur added to dried fruit. Ths is a preservative. Choose unsulphured dried fruit such as raisins or apricots. Honey can casue a problem too because it has anti-microbial properties.Preservatives in water kefir make for bad grains!
  • Are you using reactive metal utensils? Solution Make sure you are using a glass jar (not plastic) and plastic or wooden utensils. Stainless steel is ok, but I avoid metals just to be on the safe side.
  • Do you have cross contamination? Solution Don't culture different fermented foods or beverages in the same cupboard. Bacteria and yeast can become airborne and cross contaminate. This means if you have milk kefir and water kefir they should be placed in different cupboards.

If any of the above are present, and your kefir seems bad or off somehow, correct the issue, rinse your grains gently in fresh, cool water, and try making a fresh batch of water kefir. If after a few days the problem persists, then you need to take further action.

  1. Drain the grains and rinse them gently in cool fresh water.
  2. Add them to a clean glass jar
  3. Mix a sugar solution of 3 or 4 tablespoons of sugar with 2 cups of cool fresh water and add to grains.
  4. Place jar in refrigerator for 3-4 days to allow the grains to rest. Rinse the grains and change the sugar water solution daily and discard.
  5. On day 4 or 5 use the water kefir recipe  to make a fesh batch of kefir. It may take sevearl days, up to a week, to get a fresh balance batch of water kefir after rehabilitating the grains. When the grains are refrigerated, frozen or dehydrated, they go into a state of partial or full dormancy, so it may take a few batches to bring them back to health again.

Grains can be more sluggish in the winter. Try moving your culture to an inside cupboard. Cupboards along an outside wall may be quite cool and causing slower fermentation and growth of your water kefir grains.


If you see little air bubbles in your culture, and it smells lightly yeast or 'beery', be patient. These are good signs that your rehabilitation is working.

32 thoughts on “Good Grains Gone Bad”

  1. Hello,

    I acquired some milk kefir grains from a friend and have gone through the process of turning them into water kefir grains and am ready to make a batch to flavor and drink. The grains have been multiplying but each time I refresh them but there is a clear film at the top with a few little black spots, is that a concern? Do I dispose of them (which I’ve done) or are they edible?

    Off to take a swig……


    1. Hi Laura Thanks for stopping by! I have a concern about your method. You can’t convert milk kefir grains into water kefir grains. Milk kefir grains consume lactose (milk sugar) and will die off if not fed milk. Water kefir grains feed on sucrose, and can consume fructose. They are not interchangeable.
      The film and black spots at the top is a concern, and should not be there. Water kefir and milk kefir grains are edible. As they grow I usually put the excess in my smoothies.
      Kefir Nurse

  2. opps forgot to mention the Nestle water I want to use next is with Ozone? Can I use this water for my next try at getting my grains to ferment?

  3. I’m excited to have found this trouble shooting on the why’s my water kefir grains aren’t fermenting. I had my water kefir grains sleeping in the fridge with sugar while away 2x this year while on vacation and now nothing is fermenting. I tried boiled water with 1/4 cup plain sugar then boiled water with 2 tbsp of white sugar and 2 tbsp of rapadura sugar and still nothing and I even put a heating belt on (low temp) to keep it toasty while making downstairs which is cool. I don’t want to give up but man, I’ve been without the kefir water for a month now. Trying to stick to low carb/lazy keto lifestyle as well. I even did a panic thing ordering grains from but see grains come from Ireland, yikes, I think I made a mistake with that too, may have to cancel

  4. Hi…
    I left my kefir grains resting in the fridge too long. Now that I’ve checked them, they are stringy with what appears like white film or bacterial growths similar to what is called the mother in Apple cider vinegar. The sugar water isn’t thick and doesn’t smell off or bad.
    Should I even try to save these grains? I’ve rinsed them and have them soaking with lemon water.

    I was making more kefir than I could use since I live in the tropics. So if I can rehabilitate them I’ll dehydrate them for future use.
    Please advise.

  5. My friend sent me dehydrated water kefir grains months ago and since then I have struggled to make them work. I have been consistent switching them out every 48 hours. I have got a few drinkable batches but recently the liquid has become syrupy and thick and has no fizz and tastes more like sugar water than kefir. This happened before a month or two ago and i rested the grains in the refrigerator and they did ok but eventually became slimy again. I put the grains to rest again last night after giving them a good rinse. I will see what happens after a couple weeks. I use organic cane sugar and declorinated tap water. previously between each batch i would rinse the ferment jar out with hot water but should i thoroughly wash the jar with soap and hot water between each batch?

    I also had about 3-4tablespoons of grains per quart of liquid. Is that too many grains? I decreased the grains to 2 tablespoons for the next batch after the rest. When i wake the grains back up should i do a batch every 24 hrs for a week then eventually go back to 48 hrs?

    I dont have a cupboard in my kitchen to place the jars so i put them next to my fridge and cover them with multiple dish towels. my kitchen is also a little chilly in the winter. Maybe around 60 degrees. But very hot in the summer up to 80 degrees or more.

    When i declorinate the tap water i dont boil it i just leave a jar out covered in cloth for 48hrs so the chlorine evaporates. Is that a good method in your book? I am trying to be as detailed as possible so you can get a picture of the process. Thanks for all your help here!

    1. Hi Sarah Thanks for your message. I’m going to address the most likely issue here. Chlorine doesn’t evaporate when left out- just the water so you are inadvertently concentrating the chlorine. I recommend you either boil the water for 10-20 minutes and then let it cool, or use spring water that has not been chlorinated.
      If this doesn’t work to fix the issue, come on back and we will see if there are other things that need to be addressed.
      Kefir Nurse.

    1. Hi Sandy Almost always if it’s too sour, it’s over fermenting. There are lots of reasons for this. Grains ratio too high, too warm in the fermenting room, too long a ferment. With these things in mind, you will have to employ a little trial and error to get it right. Good luck!
      Kefir Nurse

  6. Hello,
    I am hoping for some direction. I have been making water kefir for a while with varying degrees of success.
    I was recently hospitalized and for 3+ weeks my kefir grains were either left in their sugar water or refrigerated. After my recovery and bringing them out and rehydrating them, I have been having issues with sulfur tasting kefir. I dump the liquid since it is so “off-putting”.
    I boil my tap water for 10 minutes before use, I changed from white sugar to Turbinado sugar. Can you help me?
    Until I can find a definitive answer I will give my grains a rest in the fridge as you suggest.
    I am missing my regular diet of kefir and no purchased kefir is comparable.

    1. Hi there I know what you mean about no store bought product being the same! It sounds like your grains need a little TLC. Follow the instructions for resting the kefir- rinshe them gently but thoroughly, put them in a solution of sugar/water and refrigerate for a week or two. Then resume and see how they are doing.
      Kefir Nurse

  7. Hello. I’ve been using Kefir water well over a year now to dilute my non-verbal, autistic son’s grape juice, 1/2 kefir water, half organic grape juice. We use glass bottles and organic sugar. We have a whole house water filtration system so the water is quite pure. The kefir water, recently, has an “eggy” odor and sometimes there is black particles floating at the top of the bottle. Very carbonated. Is this normal? Do I need to do kefir rehab? My son doesn’t seem to notice. Did I read correctly above that the kefir water needs to be replaced fully each day? Do I need to wash the kefir daily as well?
    Thank you for this information.

    1. Hi there follow the instructions for resting the kefir- rinshe them gently but thoroughly, put them in a solution of sugar/water and refrigerate for a week or two. Then resume and see how they are doing.
      Kefir Nurse

  8. Hi I made water kefir with turmeric syrup in a pinch inwards of just plain sugar and the he grains doubled but resulting kefir two batches later is more on the sour taste scale then sweet. Have I injured them beyond repair?

    1. Hi Lydia- not at all- It just sounds like they are super healthy, and over fermenting. Use fewer grains and more sugar water.
      Kefir Nurse

  9. Hello from London UK

    I love my water Kefir ! But recently it has become very ‘foamy’ as it ferments, which it used not to do. It smells fine, and I triple rinse everything so I know its not detergent contamination. But i wonder why its started doing this suddenly? Is it the higher temperatures of summer compared to the usual cooler temperatures here in England ?
    Also I get a very strong feeling of being drunk immediately after a glass of kefir (always have – same reaction w kombucha) . I have had many years of excellent diet (including pre biotic foods) and its been 2.5 years since i ve taken antibiotics (although i have a past history of multiple prolonged antibiotic usage in 2010/11 and 2015/16 for recurrent bladder infections). I assume this is a Herx reaction, but
    how long does it take to get rid of the bad bacteria and the Herx to stop ? I ve been drinking daily water kefir for over a year now. Will this ‘feeling drunk/Herx reaction stop soon ??

    Many thanks for your kind advice and greetings from the Old Country !

    1. Hi Marianne I am not convinced that feeling of euphoria is a herx reaction. We don’t really understand all the ways that the bacteria in our gut interacts with the human brain, but scientists believe that they send a flood of endorphins when they are “happy”. Usually that drunk feeling doesn’t last long- but if it is too overwhelming, try splitting your glass and drinking half in morning and half in evening. Having said that- it could indeed be a Herx reaction, and there’s no real way to tell how long it will last. Remember that the bacteria continue to grow even as some die off. Remember to eat lots of raw and cooked vegetables to encourage the establishment of the good bacteria!
      The foaming sounds to me like the yeast is growing faster- yes it could be because the spot you have it is too hot. Is there somewhere you can put it, inside, where it is still room temperature but cooler? As long as it tastes fine it won’t matter and will likely go back into balance when things cool down, but if it starts to taste yeasty you may have to refrigerate for a bit.
      Kefir Nurse

  10. I just started with water and milk kefir. Is it ok to put side-by-side during fermentation? May I know can I use the same equipment i.e. strainer, spoon and plastic container when straining the water and milk kefir?

    1. Hi Winnie You can use the same equipment if you wash well in between. I would not put them side by side, however.
      Kefir Nurse

  11. I have been making water and milk kefir for two years. My milk kefir grains grow like gang busters. My water kefir had not increased at all, and the last month is syrupy. I rinsed the grains and refrigerated them twice for a week at a time. Have used organic cane sugar the whole time, so switched to white sugar and molasses. Still syrupy. What do I try next?

    1. Hi Teresa- they’ve gotten out of balance for some reason. Follow the steps to rest and rehabilitate your grains. Make sure you are not using anything with preservatives, or chlorine.

      Kefir Nurse

  12. Hello. I am having my water kefir grains and keep fermenting it. but the problem now is that my water kefir looks like a mud. foamy and i taste a bit metallic in it. I am doing the right procedure.. clean my utensils all and all but my kefir is look like that and taste like that. can you tell me what is the problem with it. I am not drinking the kefir now. because I am afraid that it harm my health. can you please help me. I want to know what is wrong with it

  13. Hi,
    Our water kefir has developed what looks like a thick scoby on the top… It is near our kombucha so after reading about cross contamination this could be the case. We keep thinking our grains/water has gone bad but we keep making “one last batch” of flavored kefir water and it end up super carbonated and tastes great. There are very few grains left (since our original purchased grains). Each time we make our new batch the scoby floats to the bottom, then rises to the top. It is not moldy and smells fine. Do you know what is happening? Should we continue to use is? We purchased the original grains about 5 weeks ago. Should we purchase new grains and throw this out? Is there a health risk? Thank you very much!!

    1. Hi Suzie It really does sound like you have some cross contamination with the kombucha. If it tastes good, you are not in any risk for health. But here’s the thing. One of the bacteria cultures will “win”- and right now it sounds like the kombucha scoby is winning. The water kefir grains will continue to weaken- they will become unbalanced and you will start noticing some things like a thickening of the liquid, or an off taste. There may still be a window of time to save them. pour the kefir grains into a plastic or silicon strainer and rinse well with very cold water. run your fingers through the grains under the gentle water stream. put them in a fresh clean jar, cover them with cold water, add a teaspoon of sugar and put them in the fridge. Let them rest. In the meantime, sterilize all the jars you are using. and wash the utensils well with hot soapy water. After 3 days, remove the grains from the refrigerator and do your usual kefir routine, only change the sugar water and sterile jar daily for 3 days whether they brew drinkable kefir or not. After the 3rd day (you are now into this a week) switch sugar water and steril jar one more time, and allow 24 hours OR sooner if you have drinkable kefir.

      When I have kefir and kombucha brewing in the same kitchen they are separated to two far counter tops, covered always, and jars and utensils sterilized.

      If there are very few grains left, as you say, the grains will eventually disappear as the kombucha scoby bacteria win the battle, unless this rehabilitation works. 🙂

      Kefir Nurse

  14. I recently moved to an area with well-water, and had previously read that many people have great success with their water kefir on well-water so was excited to get started!
    My grains had been in the refrigerator, so I brought them out and let them get too room temperature before beginning a 1st ferment.
    I made my usual sugar water (I’ve been doing this for a few years now) and put the grains up in the cupboard. After 3 days the smell and taste of the water indicated it was ready for the 2F, however when I went to strain it out the liquid was a little thicker.
    Now through reading it seems that this means my water is too rich in minerals – there is no smell or off taste or colour in the water to indicate this – so I will likely need to bring it bottled water and perhaps mix it half and half?
    In the meantime … I am wondering if the liquid strained off is safe to consume? Does mineral rich mean not good for a 2nd ferment? Am I going to have to pour each batch down the drain until I’ve figured out a good balance?
    – Megan

    1. Hi Megan The thickness- in your case- is unlikely to be “too rich in minerals”. More likely it is simply that your grains need to be adjusted after coming out of the fridge, and a new water source. It’s most likely just that some bacteria have reactivated more uickly than others and disturbed the balance. SO- first, you need to give the grains a few more cycles and they should come back to normal. Second- the liquid- as long as it smells normal, is likely ok to drink- but personally I would discard it to be on the safe side.

      Thanks so much for your questions. Please come back in a week or two and let us know how you made out.
      Kefir Nurse

    1. Hi Helen Diabetics could benefit from drinking kefir water, but it does have sugar in it, so keep track of your sugars and adjust accordingly. If I were diabetic, I would drink some after a meal to slow down the sugar absorption and spread it out iver the day. There have been studies though, that show kefir helps regulate blood sugar (good bacteria!) 

      Kefir Nurse

  15. I let the grains sit in a jar too long without changing the milk. I took off a blue moldy skin from the top and rinsed the grains with water which I never ordinarily do. I have been soaking the grains now for a few days and changing the milk daily. What’s your feeling on this? Will my grains come back to life or has that moldy skin affected the grains so that I must now throw them out? Thanks for your help.

    1. Hi Vivian Thanks for your email. They often will survive mold! Only you will be able to make that judgement by i think if you don’t see a reappearance of mold, and the grains are fermenting then you are good to go! 

      Kefir Nurse

  16. We were making our milk kefir and water kefir and setting them on the same counter. The milk kefir seemed fine, the water kefir got a white film on it and the finished kefir was getting a slimy film on top. We gave the grains a rest but they still are a bit white. We have not been using molasses so we thought maybe the white was caused by this. Two questions, should we try again with those same grains or order new ones? Can we make water kefir without molasses? Any help you can give would be great!

    1. Hi Denise lack of molasses does not produce a white film, it simply yields a paler kefir grain. The white film indicates a sick culture. First, separate the cultures. Separated by a foot or so, as long as they are properly covered, should be fine. Now dump the grains into a bowl and rinse them thoroughly in cool water and run your clean fingers around in them. Then strain and do this several time. Now go back to the recipe and follow it word for word. I have not seen a kefir failure yet that was not a result of recipe error. Please check AL of your ingredients… non-sulphured dried fruit, NO chhlorine and minimal fluoride, a slice of lemon etc, etc. Follow it to the letter… let me know in a week or so how things look. 

      Do not ever drink kefir that is filmy, mouldy or otherwise looks off.

      Kefir Nurse

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.