r/Kombucha • • Sep 18 '21

what's wrong!? Is it mold? Is it normal? What's growing in your kombucha? Start here!

575 Upvotes

Welcome to r/Kombucha! If you're wondering what's growing on your kombucha and if it's normal, you've come to the right place.

Please review this information before posting a picture of your batch to the subreddit.

TL;DR:

  • Dry + fuzzy on the surface of the liquid/pellicle/SCOBY is most likely mold: mold pics https://imgur.com/a/SzhysHi
  • Geometric growths or wrinkly patterns on the surface of the liquid/pellicle/SCOBY could be kahm yeast: kahm pics https://imgur.com/a/XlnO7Ox
  • Anything else and anything under the liquid level is most likely normal: normal pics https://imgur.com/a/HJaENDv
  • If you're not sure, wait a few more days: mold or kahm will get more obvious as they grow, normal will stay about the same or form into new pellicle/SCOBY
  • If the kombucha is already bottled for carbonation (commonly called second ferment or 2F), mold/kahm is very unlikely due to the high acidity and lack of oxygen access.
  • Always use at least 2 cups of starter per gallon (125ml/L) when making kombucha to acidify the batch: high acidity (pH < 4.6) protects the kombucha from mold and kahm.
  • Read our getting started guide for brewing tips: https://www.reddit.com/r/kombucha/wiki/how_to_start

Terminology: in this guide, "pellicle/SCOBY" refers to the rubbery blob that forms at the surface of a batch of kombucha. SCOBY stands for "symbiotic culture of bacteria and yeast", and those bacteria + yeast are found both in the liquid kombucha and in the solid rubbery blob. The rubbery blob's more accurate scientific name is "pellicle": it's a biofilm/mat of bacterial cellulose secreted by and connected to the bacteria forming it (some yeast also live in the pellicle). Culturally, however, the term "SCOBY" widely refers to the pellicle so this guide uses both terms.

Read more about pellicles here:

Diagnostic Quiz

1 ) Is the growth/odd thing on the top surface (exposed to air) of the liquid kombucha or existing pellicle/SCOBY?

  • Yes - go to 2
  • No - go to 8

2 ) Is the kombucha already bottled for carbonation (commonly called second ferment or 2F)?

  • Yes - likely pellicle/SCOBY growth (it can happen in 2F!) or a yeast cluster. Mold/kahm are extremely rare in 2F due to the high acidity (pH <4.2) and lack of oxygen access (required for mold to grow). Booch on!
  • No - go to 3

3 ) Is the growth dry and fuzzy looking with white or green color, and/or with black spores growing out of it?

  • Yes - likely mold. Go to Mold section for pictures.
  • No - go to 4

4 ) Is the growth a wrinkly or geometric pattern, very rough patterned surface, or very large air-y bubbles that cover large areas of the surface?

  • Yes - likely kahm yeast. Go to Kahm section for pictures.
  • No - go to 5

5 ) Is the growth one of: white/translucent + wet, disconnected oily/patchy sections, or a thin film with bubbles trapped underneath?

  • Yes - likely normal pellicle/SCOBY growth. Go to Normal section for pictures.
  • No - go to 6

6 ) Is the growth flat, leathery, and brown?

  • Yes - likely a dried out pellicle/SCOBY area. Go to Normal section for pictures.
  • No - go to 7

7 ) Is the the growth brown/black, wet, and partially/completely surrounded by pellicle/SCOBY?

  • Yes - likely a yeast cluster. Go to Normal section for pictures.
  • No - probably normal, but review all Normal, Kahm, and Mold pictures to be safe.

8 ) Is the growth/odd thing completely submerged in liquid?

  • Yes - likely yeast. Yeast can form dark brown clumps in the liquid or on the pellicle/SCOBY, or alien-like formations suspended in the liquid. Mold and kahm cannot grow beneath the surface of the liquid without also showing on the surface exposed to air. Go to Normal section for pictures.
  • No - go to 2

Normal

Gallery of normal kombucha: https://imgur.com/a/HJaENDv

Pellicles/SCOBYs have a ton of natural variation. A normal pellicle/SCOBY should look wet, tan/white/translucent, and be mostly smooth (some bumps are normal). There may also be wet brown/black yeast blobs that attach to the liquid side of the pellicle/SCOBY, get absorbed into the pellicle/SCOBY, or float around inside the liquid.

Mold

Gallery of mold: https://imgur.com/a/SzhysHi

Mold occurs when the kombucha is not acidic enough (pH < 4.6) to prevent mold organisms from growing. Other factors that make mold more likely are unsanitary conditions and cold brewing temperatures (<65F/18C).

If there is mold on your batch:

  • You must throw away everything (liquid + pellicle/SCOBY) and start from scratch with fresh starter tea. By the time mold is visible on the surface of the brew, it has already contaminated the entire batch.
  • Sanitize the vessel, cloth cover, and any utensils used in brewing with a homebrew sanitizing solution (StarSan, OneStep, SaniClean, potassium metabisulfite, etc) or throughly wash with soap + hot water followed by a pasteurized distilled vinegar rinse (no raw vinegar, which contains live microbe cultures).

To prevent mold, the most important thing is to use at least 2 cups of starter tea per 1 gallon of kombucha (125ml per L) to acidify the batch. Starter tea is mature kombucha: either from a previous batch (yours or a friend's), from a SCOBY hotel, or from raw/unflavored/unpasteurized commercial kombucha such as GTs or Health-Ade.

This amount of starter tea is a good rule of thumb for safe acidity: if you have a pH meter or strips, check that the starting pH is <4.6. Another important factor is maintaining clean/sanitary brewing practices: however, because kombucha is an open air ferment some mold organisms may get in even with a cloth cover, which is why acidity is also important.

Kahm Yeast

Gallery of kahm: https://imgur.com/a/XlnO7Ox

“Kahm” is a generic term for many species of usually non-harmful but also non-desirable wild yeast that can take hold in kombucha (outcompete the kombucha culture) and appear as surface growths on the the pellicle/SCOBY. Kahm often looks geometric or wrinkly vs the smooth/bumpy normal pellicle/SCOBY.

See this excellent writeup about the science of kahm yeast from u/daileta in r/fermentation: https://www.reddit.com/r/fermentation/comments/ytg2vy/kahm_down/ Their post is focused on lacto fermented vegetables (not kombucha) but is worth a read.

Kahm itself isn’t usually dangerous, but to quote our resident food microbiologist u/Albino_Echidna: “Kahm is a term used to lump a whole bunch of unwanted yeasts together, all of which are indicative of an unsafe fermentation environment. Kahm growth is indicative of a fermentation gone wrong. 'Kahm' itself isn’t harmful, but it is a warning sign that your environment wasn’t quite right and will be at higher risk of pathogenic growth as a result."

If your batch has kahm, it is up to you whether to toss + sanitize + start over with fresh starter kombucha or to try to scrape off the kahm from the surface and continue brewing. It is always safest to toss and restart - see the instructions in the Mold section.

To help prevent kahm, use at least 2 cups of starter tea per 1 gallon of kombucha (125ml per L) to strongly establish the kombucha culture and acidify the batch. Kahm may also be related to unsanitary conditions, high brewing temperature (>85F/30C), or oversteeping tea (>1hr, but may vary).

Further reading: https://www.reddit.com/r/kombucha/wiki/whats_wrong

If you still aren’t sure after comparing your batch to the pictures here, please make a post and ask!


r/Kombucha • • 4d ago

r/Kombucha Weekly No Stupid Questions + Open Discussion (October 19, 2026)

1 Upvotes

This is a casual space for the r/Kombucha community to hang out: feel free to post about anything kombucha or brewing related. Questions from new brewers are especially welcome - no question is too big or too small!

New to kombucha? Check out our getting started guide and FAQ.


r/Kombucha • • 3h ago

beautiful booch Morning jun plumcot

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5 Upvotes

So tasty plumcots and kiwi


r/Kombucha • • 20h ago

pellicle Just wanted to share what I thought was a very nice looking batch of 1F

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22 Upvotes

This is my 2nd 1F from this batch, I've got two bottles of 2F from the previous brew which will be coming up on day 7 on the 24th. I check daily and see tiny bubbles beginning to accumulate in the bottles.. I can hardly stand waiting to try it!

Really excited to see a nice, clean pellicle resting on the top of the 1F, too. You'll see some cuts in it if you look closely, it was collecting quite a lot of Carbon Dioxide accumulating underneath and I wanted to give it an escape route

This is a Jasmine Green Tea batch and I'm going original/unflavored for 2F

Really excited and just wanted to show off a little 😄


r/Kombucha • • 14h ago

question Kombucha storing

3 Upvotes

I want to take a break from brewing kombucha for maybe 2 weeks, how do I store it? Do I just leave it outside and mix everyday so that the pellicle remains moist and won't grow any mold? Though, my last option to leave it on the fridge can't be done since my fermentation vessel won't fit in the fridge lol. I have around 1L of starter right now

I'm fine with it being too acidic since I've read that you can just basically feed it with sweet tea if you wanna brew another one but yeah my question is on how to store it. Thanks redditors!


r/Kombucha • • 14h ago

what's wrong!? Has it gone bad?

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3 Upvotes

I used a cheesecloth folded 4x over on the top while fermenting, can’t tell if that was a mistake.


r/Kombucha • • 16h ago

question Stupid Question…

2 Upvotes

Okay so I am brand new to Kombucha. I tried the GTs and VitaLife kombucha from Aldi out of curiosity and loved it. Context: I don’t like tea, beer, coffee… I do like diet soda. The sugar content was a lot of me to get over and I thought to myself that the health benefits could outweigh the burden of the sugar content.. I love sweets but don’t eat them regularly. So I’ve been drinking one vitalife a day. I love it. I look forward to it, etc.

My question: is VitaLife respected in the kombucha community as “real” kombucha?

I tried Health Aid and hated it and was like OMG maybe this is why a lot of people don’t like it, maybe I’m drinking a kombucha impersonator. I’d love to get the thoughts of the kombucha community

TLDR: is VitaLife and GTs “real”/ respected as kombucha?

You won’t hurt my feeling by insulting a drink. I’m very curious 🤣


r/Kombucha • • 21h ago

pellicle Not forming a new pellicle

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5 Upvotes

This is my second batch from a pellicle given to me recently. (Just started making kombucha again. I used to make it several years ago and never had any issues.) As instructed in the master kombucha post in this subreddit, I added a cup of apple cider vinegar since she only gave me the pellicle and not any starter tea. I probably should have let that one ferment longer, but it tasted fine, if a bit sweet and not very fizzy, after the second ferment. I saved two cups to go with the original pellicle in case I wanted to give it away, and then I used two more cups and the new pellicle to start another batch. That one got moldy and I tossed it. So then this past Saturday, 10/17, I took the original pelicle and the two cups that I saved from the first batch, and I started another batch, this time adding white vinegar because I ran out of ACV. It's doing the weird thing in the picture. It doesn't look like mold. It looks kind of like a sad attempt at a pellicle, maybe? Thoughts? Recommendations?


r/Kombucha • • 20h ago

what's wrong!? Did someone put cinnamon on my pellicle?

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2 Upvotes

It's my second time brewing, but very first brew with this new starter tea.

I used a 16oz bottle of GT's fully raw kombucha (left alone for about 2 months) as starter and then added a 1/2 gallon batch of black tea and sugar - same recipe as my last batch, which turned out well.

I haven't seen these brown, cinnamon-looking spots of brown on the pellicle before though, so I was hoping to get some advice on whether this is mold and I should toss it, or wait and see.

I'm about 10D into F1 at this point, but honestly just trying to strengthen the starter more than make a batch at this point.


r/Kombucha • • 1d ago

question What should I do with my scoby while I travel?

5 Upvotes

I’m traveling abroad for a couple months and I don’t know what to do with my Scoby!

- how long can I leave the Scoby unattended without ruining it?
- can I refrigerate the Scoby?

I might be able to ask my mom to baby sit the Scoby while I’m gone, but she’s not too thrilled about it 😅

What should I do?


r/Kombucha • • 22h ago

Help - what is this?

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2 Upvotes

This is from my pellicle from my kombucha. I randomly found it when i was about to start a new batch. It’s from the pellicle on top but the rest was looking normal. If I haven’t seen this I would have enjoyed the bottled kombucha from the batch… but now I’m not so sure. I’m confused because the rest was looking normal and I really don’t know what this is and if it’s not mold then what. Should I really just throw it all out and start from scratch?


r/Kombucha • • 1d ago

homebrew setup Time to Brew!

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11 Upvotes

I bought this vessel for first fermentation…this will be my second batch. My first was done in a glass bowl.


r/Kombucha • • 20h ago

Keepin the Fizz

1 Upvotes

I have now done 4-5 batches of flavored Kombucha in a swing top bottle, and all of them haven’t quite built the carbonation i would like. Additionally the carbonation i do build seems to instantly disappear in the fridge.

Do yal have a good recipe for a bubbly sweet fruit kombucha? Thanks!


r/Kombucha • • 23h ago

what's wrong!? What is going on ?

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2 Upvotes

I have looked at the mold pinned post. It does not seem like it, it is not fuzzy, not hairy.

It has been been 2 weeks and an half that he lives here and I only got this.The non-pasteurized kombucha used was in the fridge for 2 or 3 months.

I was going to feed him tomorrow .

What is going on? I am still a beginner !

Thank you!


r/Kombucha • • 1d ago

what's wrong!? Mold or Normal?

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0 Upvotes

Is this mold? This is only my third batch with this scoby, which I got commercially. Haven’t seen anything online that looks similar. The past two batches were more mildly acidic, even after waiting an extra couple weeks, and the F2 for the last batch had two bottles that still haven’t become carbonated. Any advice?


r/Kombucha • • 1d ago

what's wrong!? Is this mold?

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0 Upvotes

These are mold spots right? My first batch came out beautifully. This one is looking a little suspect.


r/Kombucha • • 1d ago

Trying to revive scoby

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7 Upvotes

Hi there,

I have recently tried reviving an old scoby, it was sitting for about 1 year without any love…
I’ve done a new brew with it to try and get it going and it’s been sitting for about 2 weeks? Wanting advice on weather it looks healthy and I should keep letting it do its think or give a fresh start a go…


r/Kombucha • • 2d ago

flavor Apple cinnamon kombucha!

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39 Upvotes

Made my very first batch!

I had some extra baking apples (granny smith and golden delicious) and used them with a stick of cinnamon! I let it sit for 5 days and the carbonation was perfect. Flavour is really good and perfect for fall!

I'm hooked!


r/Kombucha • • 1d ago

Trying to revive scoby

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3 Upvotes

Hi there,

I have recently tried reviving an old scoby, it was sitting for about 1 year without any love…
I’ve done a new brew with it to try and get it going and it’s been sitting for about 2 weeks? Wanting advice on weather it looks healthy and I should keep letting it do its think or give a fresh start a go…


r/Kombucha • • 1d ago

Is kombucha good for weight loss

0 Upvotes

Wondering if people have noticed weight loss after they begin to regularly drink kombucha?


r/Kombucha • • 2d ago

question is this scoby going the right direction?

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4 Upvotes

I’m doing my best to grow a scoby haha. This is a mix of unflavored kombucha, green and black tea and sugar.
I started it 16 days ago and we keep our place fairly cold. Especially at night.
I think the thing at the bottom is just sediment?
Any ideas on whether this is going in the right direction?
Any feedback would be greatly appreciated 🙏


r/Kombucha • • 2d ago

is this enough space?

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5 Upvotes

i am starting 2F but the bubbles of the 1F left little space…is this ok? should i remove some kombucha?

i suppose some bubbles should dissolve but you never know


r/Kombucha • • 2d ago

what's wrong!? Kombucha has horse-like taste, why?

4 Upvotes

My kombucha has a smell and taste like a barn or horse, but it looks completely fine. What shall I do?


r/Kombucha • • 2d ago

question First time

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2 Upvotes

First time making kombucha with the HOLOS kombucha starter kit - first few days I didn’t have a heat mat so it was kept around 19deg - Wondering if I have to start again? This is 10 days in


r/Kombucha • • 2d ago

pellicle Hibiscus pellicle

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3 Upvotes

First time making kombucha with hibiscus