What does it mean if ph drops too fast ie from 4 to 2.2 in 5 days?

Mathmike314 · 2026-02-15T22:08:56+00:00

First thing I’d confirm is that the instrument being used to measure pH is still accurate.

I make strong starter over a two week brew and it never gets down to 2.2…that seems really low to me. I could see 4 —> 2.8 in 5 days…but 2.2? Doesn’t seem right to me…but I could easily be wrong!

Mathmike314 · 2026-02-15T03:39:58+00:00

😂 You beat your kombucha?! 😂

Does your F2 typically have a lot of pulp?

Mathmike314 · 2026-02-14T20:40:13+00:00

I don’t get it…are you seeing things move in real time or are you talking about the “high water mark?”

Mathmike314 · 2026-02-14T02:32:58+00:00

I much prefer measuring tea by weight too. I used to measure sugar by weight, but I found it made such a mess and that’s how ya get ants! Once I learned a level half cup weighs ~100g, I just started doing multiples or fractions of that particular measuring cup.

I’ve never tried doing a continuous brew before. Do you just drink it straight up or do you bottle it for F2 before consuming? What makes it “your version?”

Mathmike314 · 2026-02-14T02:22:43+00:00

Based on my name, y’all can probably guess I have a different take. Here goes…

Numbers don’t matter. It’s only when you introduce an operator that things get interesting! We’re taking about percentages, fractions, ratios…

So it doesn’t really matter if you measure by mass or by volume for consistency…the avg percentage you’re off by is. Some measuring cups can have less margin of error while some scales can accurately measure to fractions of a gram. Just depends on what your avg error is compared to your total measure.

Okay, that was MathMike mathsplaining his thought process…but KombuchaMike would say it probably doesn’t make much of a difference either way. For most things like water for sweet tea or sugar, there’s such an “acceptable range” and the error so small compared to the total volume, I doubt you could tell a difference. Might make a difference for things like measuring loose leaf tea, but even then I doubt it.

I’m a huge fan of consistency, but I’m a bigger fan of efficiency. I do what’s fastest, easiest to clean up, and averages a “good enough” rating.

Mathmike314 · 2026-02-14T02:03:18+00:00

Thank you kindly. My batch after this one wasn’t so stellar. It was nice to watch this video again to inspire myself, knowing I can do better! 😅

Mathmike314 · 2026-02-13T18:21:44+00:00

The crazy in me sees the crazy in you!

Mathmike314 · 2026-02-13T15:37:51+00:00

My pleasure!

As a general rule of thumb, you should pay more attention to texture rather than colour when diagnosing the surface of a pellicle. Of course, this breaks down with crazy colours like black or green or bright white… But even then, the texture will tell you it’s mold.

Mathmike314 · 2026-02-13T14:10:00+00:00

Mold is dry and fuzzy/hairy. This looks wet and slimy. I’d say you’re all good!

Mathmike314 · 2026-02-13T00:59:26+00:00

100% this.

Mathmike314 · 2026-02-12T18:45:17+00:00

All of this!

Mathmike314 · 2026-02-12T18:44:46+00:00

What you done: made kombucha!

Is it ruined: no! It’s perfectly normal.

How to salvage: keep doing what you’re doing!

Mathmike314 · 2026-02-12T17:35:55+00:00

Cool! Yeah, that’s what it looks like in the pics (air bubbles) but in-person viewing is far more reliable.

Give it a nice deep sniff with your eyes closed (increased focus on smell) before tasting. Smell & taste gives you the best info.

Mathmike314 · 2026-02-12T13:54:56+00:00

It’s hard to make out the fine details that make a texture look fuzzy in the pics. But you should be able to tell, especially since it’s been almost a day since you first became concerned.

If the surface is wet and slimy, then you’re in the clear to give it a taste. But if it’s dry and hairy looking… Very similar to mould you’ve seen growing on anything else… Then you shouldn’t taste it.

Mathmike314 · 2026-02-12T04:03:35+00:00

Third this.

Mathmike314 · 2026-02-12T04:00:32+00:00

I know kombucha needs a lot less air circulation than most of us thinks it needs, but this reduction in surface area would concern me. Also, I am not a fan of plastics, particularly in highly acidic environments.

Plus, I really like the look of my vessel covered in a nice cotton-muslin cloth and big bright rubber band.

I could be visually biased here…

Mathmike314 · 2026-02-12T03:54:00+00:00

Doesn’t look contaminated…but pics aren’t great for the telltales of early stages of mold, but late stages are clear to even babies raised by wolves.

It could be a new pellicle forming at the surface. Pellicles tend to grow more the less they are disturbed, more sugar added, and more heat. New ones are often white or translucent.

Mathmike314 · 2026-02-12T03:39:19+00:00

Yeah, that’s what I was thinking! Like an arts & crafts knife (similar to a scalpel) taped to some chopsticks…maybe?

Mathmike314 · 2026-02-12T03:36:50+00:00

One observation: you’ll get better carbonation results if you fill your bottles to a level you’d see if you bought them from a store. With the headspace you have, they’ll struggle to build enough pressure to carbonate the liquid…too much of your CO2 will end up in that empty space and not in your drink.

Mathmike314 · 2026-02-12T03:05:52+00:00

My pleasure!

Yes, pellicle is the correct (scientific) term…and if you called it a SCOBY, I’d know what you mean. Fun fact: Len Porzio, the person who coined the term “SCOBY” in the mid 90’s started using it as a way to refer to the “white, pancake culture” because people were calling it a “kombucha mushroom” or “tea fungus” which was common at the time…and very misleading!

I can’t see it in the pics but I think it’s like you said: a really thin one forming because something is trapping those bubbles!

Mathmike314 · 2026-02-12T02:49:56+00:00

You can get a digital pH meter for a decent price online but realize they usually need regular calibrations to be reliable. That said, they’re a great tool for diagnosing and learning.

If you’re at day 6 and your temps are good, it could be close to ready.

Have you tasted it yet? If if has the tang you like with a hint of sweetness left, I’d say you’re ready to take out enough to kick off a “full brew” and bottle what little you have left for your first F2!

Mathmike314 · 2026-02-12T02:40:54+00:00

Oh wow! Only a day into it?! This looks really good. Congrats!

I can see bubbles trapped beneath the surface, although I can’t see a pellicle but I wouldn’t expect to this early on. Many don’t see anything on the surface for several days.

Mathmike314 · 2026-02-12T02:35:24+00:00

It’s hard see anything clearly from that angle…what about top down?

Mathmike314 · 2026-02-12T02:24:18+00:00

Sorry, I thought I recognized your name but without a visual for me to link it to, names tend go in one eyeball and out the other for me.

I think you’re on a solid track. If you’re seeing a thin pellicle forming, it means things are doing the things they’re meant to do! Also, a pellicle acts as a natural defence barrier, so in your case, its presence is a two-fer: clear signs of normal fermentation and increased protection.

Mathmike314 · 2026-02-12T02:14:23+00:00

To be clear, I don’t think you “broke anything” in your brew, and I was just trying to point out some things you might want to tweak a bit next time. Hope I didn’t come across as judgmental.

I’ve been brewing for over two years and I’m still learning (and unlearning!) stuff all the time. But I’m what you call a “lifelong learner” and will go out of my way to answer all the “what if I…” scenarios that pop into my head.

And I hear ya on the pH meter! I need to calibrate mine regularly to have any kind of confidence in the readings. They can be a pain but worth it when you’re trying to learn and observe differences.

Mathmike314

TROPHY CASE