If you carbonate kombucha, pop, cider, or spritzers, your bright-tank problem is different from a brewer’s: your product arrives warm.
The warm-tank problem
On a real kombucha plot, the product hit the tank at over 12 degrees Celsius, far too warm to carbonate. You want the product as close to 0 degrees as possible for CO2 to dissolve. So the first job is patience: chill before you carbonate.
Start temperature and the mixing bounce
FizzWizz’s start temperature setting is typically 3.5 degrees; this client set 5. At 5 degrees a little pre-scrubbing is acceptable, but carbonation is not, and neither should run while the product is properly warm. When the CO2 first kicks on, it stirs the tank. Warmer product drawn down around the temperature sensor makes the reading jump, the unit pauses, then restarts as the tank mixes and chills. You’ll see that little disturbance on the plot. It’s normal and it resolves itself.
The vacuum trap
As a warm tank chills, the pressure inside falls. Drop it carelessly and you can pull a vacuum on the tank. The clean solution this client used: leave about 1.5 PSI in the tank as a floor, so the temperature drop can never take it negative. On this run the chill pulled the tank down by nearly half a PSI, so that floor left plenty of margin. It’s also worth confirming your tank’s vacuum relief valve is correctly sized and working: a tank fails when the pressure difference exceeds its external rating (Paul Mueller).
Then it’s automatic
Once the product is down to temperature and stable (2.29 degrees on this plot), the pre-scrub runs (target 3 PSI, then vent to 1 PSI) and carbonation starts on its own, with no buttons to press. This run shut off at 11.24 PSI against a target of 11.22: within 0.02 PSI, with the target continuously recalculated as the tank temperature moved. All you decide is when to turn the FizzWizz on, so the chill, pre-scrub and carbonation fit your schedule.
Typical carbonation targets
If you’re setting volumes for a non-beer product, these published ranges are a useful starting point (University of Florida IFAS):
| Drink | Volumes of CO2 |
|---|---|
| High-carbonation soda (cola) | 3.5 to 4 |
| Club soda and tonic | 2.5 to 3.5 |
| Lemon-lime soda | 2.5 to 3.5 |
| Typical lager | 2.4 to 2.6 |
| Champagne | 4.6 to 6 |
Kombucha and cider vary by style and aren’t covered by that source, so set your own target to suit your product.
Carbonating anything besides beer? Talk to us about your product. We regularly help set up kombucha, cider and soda tanks.