# Kombucha Thermostat with CircuitPython and Feather ## Overview Hi, [Rebecca Minich](https://rebeccaminich.com/) here! I'm moonlighting as the CircuitPython wiz Scott Shawcroft today so I can share my Kombucha thermostat project. If you are a fan of sour, this fermented drink might be for you. Unfortunately, it comes with the health food price tag of $3/bottle. Brewing it is much cheaper and way more fun! For a healthy culture and delicious tasting 'buch you'll need to maintain a pretty high temperature (~77F/25C) while brewing (5-7 days). Keeping the brew that warm is challenging in colder climates. With a little help from a terrarium heater and some electronics, I created a thermostat for brewing year round. Check it out below!   ![](https://cdn-learn.adafruit.com/assets/assets/000/038/851/medium800/temperature_schematic.jpg?1485915079) ## Parts Required ## 1. FOR KOMBUCHA BREWING: - [Glass/Ceramic container](https://smile.amazon.com/gp/product/B0139APG2O/ref=oh_aui_detailpage_o01_s01?ie=UTF8&psc=1): I highly recommend a container with a spigot.  - [SCOBY and starter liquid](https://smile.amazon.com/gp/product/B009ZW8RP4/ref=oh_aui_detailpage_o07_s02?ie=UTF8&psc=1): I bought my SCOBY from a local vendor but I've used this one too. - [Green](https://smile.amazon.com/gp/product/B001E5E38K/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1) or[black tea](https://smile.amazon.com/gp/product/B003SO4JBG/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1)  - Sugar: When first starting out it's best to use regular white cane sugar  ##   ## 2. FOR KOMBUCHA THERMOSTAT: - [Terrarium heater](https://smile.amazon.com/gp/product/B00TR6AA5I/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1): I have this one but any low output heater will do. - [PowerSwitch Tail 2](https://www.adafruit.com/products/268)   - [Adafruit Feather](https://www.adafruit.com/products/2796):  I used the Adalogger in case I decide to store temperature data.  - [High Accuracy Temperature Sensor Breakout Board (MCP9808)](https://www.adafruit.com/products/1782): AKA thermometer - [Micro USB to USB cord](https://www.adafruit.com/products/2008) and [AC wall adapter](https://www.adafruit.com/products/1994):  An old phone/kindle charger works fine.   - [Jumper Extension wires](https://www.adafruit.com/products/826) - [Wire Spool (optional)](https://www.adafruit.com/products/1311): Depending on your Kombucha setup you may need extra long connectors. I used wire spool between my Feather and my PowerSwitch Tail.  - Misc: [Small Phillips head screwdriver](https://www.adafruit.com/products/3284), electrical tape, infrared thermometer. - [Next Page](https://learn.adafruit.com/kombucha-thermostat-with-circuitpython-and-feather/hardware-setup.md) ## Featured Products ### Adafruit Feather M0 Adalogger [Adafruit Feather M0 Adalogger](https://www.adafruit.com/product/2796) Feather is the new development board from Adafruit, and like its namesake it is thin, light, and lets you fly! We designed Feather to be a new standard for portable microcontroller cores. This is the  **Adafruit Feather M0 Adalogger**  - our take on an... In Stock [Buy Now](https://www.adafruit.com/product/2796) [Related Guides to the Product](https://learn.adafruit.com/products/2796/guides) ### Header Kit for Feather - 12-pin and 16-pin Female Header Set [Header Kit for Feather - 12-pin and 16-pin Female Header Set](https://www.adafruit.com/product/2886) These two  **Female Headers**  alone are, well, lonely. But pair them with any of our [Feather](https://www.adafruit.com/categories/777) boards and you're in business! What do they do? They get soldered on either side of the Feather... Out of Stock [Buy Now](https://www.adafruit.com/product/2886) [Related Guides to the Product](https://learn.adafruit.com/products/2886/guides) ### Powerswitch tail 2 [Powerswitch tail 2](https://www.adafruit.com/product/268) [**The PST has been discontinued. Please check out the IoT Power Relay for an equivalent alternative. The IoT Power Relay has more outlets but otherwise is functionally the same, and at a similar price!**](https://www.adafruit.com/product/2935) The Power Switch... No Longer Stocked [Buy Now](https://www.adafruit.com/product/268) [Related Guides to the Product](https://learn.adafruit.com/products/268/guides) ### MCP9808 High Accuracy I2C Temperature Sensor Breakout Board [MCP9808 High Accuracy I2C Temperature Sensor Breakout Board](https://www.adafruit.com/product/1782) This I2C digital temperature sensor is one of the more accurate/precise we've ever seen, with a typical accuracy of ±0.25°C over the sensor's -40°C to +125°C range and precision of +0.0625°C. They work great with any microcontroller using standard i2c. There are... In Stock [Buy Now](https://www.adafruit.com/product/1782) [Related Guides to the Product](https://learn.adafruit.com/products/1782/guides) ### Food-Grade Heat Shrink - 3/8" diameter 12" long [Food-Grade Heat Shrink - 3/8" diameter 12" long](https://www.adafruit.com/product/1020) We decided to stock this food-safe heat shrink specifically for people who were building beer-brewing or sous-vide projects using our [waterproof DS18B20+ digital temperature sensors](http://www.adafruit.com/products/381). This heat shrink is FDA Compliant for contact with food. The... In Stock [Buy Now](https://www.adafruit.com/product/1020) [Related Guides to the Product](https://learn.adafruit.com/products/1020/guides) ### High Temp Waterproof DS18B20 Digital temperature sensor + extras [High Temp Waterproof DS18B20 Digital temperature sensor + extras](https://www.adafruit.com/product/642) This is a pre-wired and waterproofed version of the DS18B20 sensor made with a PTFE wire cable. Handy for when you need to measure something far away, or in wet conditions. This sensor is a little more expensive than [the other waterproof version...](http://www.adafruit.com/products/381) In Stock [Buy Now](https://www.adafruit.com/product/642) [Related Guides to the Product](https://learn.adafruit.com/products/642/guides) ### Waterproof 1-Wire DS18B20 Digital temperature sensor [Waterproof 1-Wire DS18B20 Digital temperature sensor](https://www.adafruit.com/product/381) This is a pre-wired and waterproofed (with heat shrink) version of a 1 Wire DS18B20 sensor. Handy for when you need to measure something far away, or in wet conditions. While the sensor is good up to 125°C the cable is jacketed in PVC so we suggest keeping it under 100°C. Because they... In Stock [Buy Now](https://www.adafruit.com/product/381) [Related Guides to the Product](https://learn.adafruit.com/products/381/guides) ### USB Patterned Fabric Cable - A/MicroB [USB Patterned Fabric Cable - A/MicroB](https://www.adafruit.com/product/2008) Oooh it's so soft! And that beautiful pattern! If you have to have visible cables then you might as well have the nicest fabric bound cable with a eye-catching snake-like pattern.  That's why we now carry this standard A to micro-B USB cable for USB 1.1 or 2.0.... No Longer Stocked [Buy Now](https://www.adafruit.com/product/2008) [Related Guides to the Product](https://learn.adafruit.com/products/2008/guides) ## Related Guides - [Adafruit Feather M0 Adalogger](https://learn.adafruit.com/adafruit-feather-m0-adalogger.md) - [My Mini Race Car](https://learn.adafruit.com/my-mini-race-car.md) - [MCP9808 Temperature Sensor Python Library](https://learn.adafruit.com/mcp9808-temperature-sensor-python-library.md) - [Monitor Your Greenhouse with a No-Code Environmental Sensor](https://learn.adafruit.com/monitor-your-greenhouse-with-a-no-code-environmental-sensor.md) - [Wearable Continuous Temperature Monitor with Adafruit IO](https://learn.adafruit.com/wearable-temperature-monitor.md) - [Programming an M0 using an Arduino](https://learn.adafruit.com/programming-an-m0-using-an-arduino.md) - [MicroPython for SAMD21](https://learn.adafruit.com/micropython-for-samd21.md) - [No-Solder LED Disco Tie with Bluetooth](https://learn.adafruit.com/no-solder-circuit-playground-bluetooth-disco-tie.md) - [Monitor PiCam and temperature on a PiTFT via adafruit.io](https://learn.adafruit.com/monitor-picam-and-temperature-on-a-pitft-via-adafruit-dot-io.md) - [CircuitPython Hardware: SD Cards](https://learn.adafruit.com/micropython-hardware-sd-cards.md) - [Debugging the SAMD21 with GDB](https://learn.adafruit.com/debugging-the-samd21-with-gdb.md) - [Data Logging IoT Weight Scale](https://learn.adafruit.com/data-logging-iot-weight-scale.md) - [Speech Synthesis on the Raspberry Pi](https://learn.adafruit.com/speech-synthesis-on-the-raspberry-pi.md) - [Simple Vertical Wordclock](https://learn.adafruit.com/vertical-wordclock.md) - [Using ATSAMD21 SERCOM for more SPI, I2C and Serial ports](https://learn.adafruit.com/using-atsamd21-sercom-to-add-more-spi-i2c-serial-ports.md) - [CircuitPython Hardware: PCA9685 DC Motor & Stepper Driver](https://learn.adafruit.com/micropython-hardware-pca9685-dc-motor-and-stepper-driver.md)