Midwest Grow Kits
Bonsai 25Q Fully Automatic Electric Pressure Sterilizer Autoclave 110V
Bonsai 25Q Fully Automatic Electric Pressure Sterilizer Autoclave 110V
Bonsai 25Q Tabletop Autoclave – Fully Automatic Benchtop Steam Sterilizer
The Bonsai 25Q is a compact benchtop autoclave built for people who sterilize every week and are tired of babysitting a stovetop pressure cooker. Set your temperature, set your time, walk away. It reaches sterilization pressure in about 25 minutes on a standard 110V outlet, holds 15–20 PSI, and alarms when the cycle is done.
We are not guessing about this one. We run four Bonsai 25Q units daily in our own production lab in Woodstock, Illinois — sterilizing liquid culture, agar, grain jars, spawn bags, and tools.
- Capacity25 Quart
- Power110V / 2kW
- Pressure15–20 PSI
- To pressure~25 min
- Fits14 qt jars
Why This Unit Instead of a Stovetop Pressure Canner
A stovetop canner works, but it needs a burner, constant attention, and manual pressure management for every load. The 25Q is a sealed electric unit with its own heating element and digital control. The practical difference is not sterilization quality — both reach 121°C — it is what you do during the cycle.
| Bonsai 25Q | Stovetop Pressure Canner | |
|---|---|---|
| Heat source | Built-in 2kW element, 110V outlet | Your stove or a propane burner |
| Pressure control | Automatic, digital setpoint | Manual — you watch the gauge |
| Attention required | Load, set, walk away | Monitored for the whole cycle |
| Cycle end | Auto shut-off plus audible alarm | You have to be there |
| Stove tied up | No | Yes, for hours |
Where it sits in the lineup. The 25Q is the step up from a pressure canner and the step before a floor-standing commercial unit. If you are running more than a few dozen bags a week, look at the commercial autoclaves instead. If you are still deciding, the full autoclaves and pressure cookers range covers both ends.
Full Specifications
| Specification | Detail |
|---|---|
| Chamber capacity | 25 quarts (approximately 23.7 liters) |
| Construction | 100% stainless steel |
| Heating element | 2kW |
| Electrical | 110V standard household outlet |
| Working pressure | 15–20 PSI |
| Temperature range | 105–126°C (221–259°F) |
| Time to pressure | Approximately 25 minutes |
| Controls | LED control panel — set temperature and hold time |
| Safety | Double safety valve, automatic shut-off, cycle completion alarm |
| Lid | Quick-latch hand wheel |
| Included | Removable stainless steel basket, aluminum bottom grate |
| Drainage | Water drain outlet |
| Shipping weight | 38 lbs |
| Warranty | 1 year, U.S.-based support |
What Fits Inside
The chamber is tall and narrow rather than wide, which is what lets it take a full rack of quart jars standing upright.
| Load | Capacity per cycle | Typical cycle time |
|---|---|---|
| Wide-mouth quart jars (grain) | Up to 14 | 90 minutes at 121°C |
| Liquid culture jars | Up to 14 | 25–30 minutes at 121°C |
| Agar media flasks | Varies by vessel | 25–30 minutes at 121°C |
| Tools and utensils | Loose in basket | 25–30 minutes at 121°C |
Running a Cycle
- Remove the inner stainless steel basket and disconnect the lid tubing.
- Place the aluminum grate in the bottom of the chamber.
- Add purified water — enough to cover the heating elements, roughly 1cm below the bottom tray.
- Load your jars, bags, media, or tools.
- Close the lid and tighten the hand wheel knob.
- Set the temperature to 121°C (250°F) and enter your hold time.
- Start the cycle. The timer begins once the chamber reaches the setpoint, equivalent to roughly 15–17 PSI.
- Wait for the completion alarm, then vent and unload.
Water matters. Use purified or RO water. Hard tap water will scale the heating element over time and shorten its life. This is the single most common maintenance mistake we see.
Safety Features
- Double safety valve system — redundant over-pressure protection
- Automatic shut-off — the unit powers down the element at cycle end
- Completion alarm — audible signal so a finished cycle is never left sitting
- Quick-latch hand wheel — positive lid engagement before pressure builds
Shipping, Support and Warranty
- Free shipping within the lower 48 — the unit ships parcel at 38 lbs, no freight required
- 1-year full warranty
- U.S.-based technical support at support@midwestgrowkits.com — we run these units ourselves, so questions get answered by people who use them
- Replacement gaskets and seals are stocked domestically
Frequently Asked Questions
Is the Bonsai 25Q a true autoclave or just a pressure cooker?
It is a true steam autoclave. It reaches and holds 121°C at 15–20 PSI with automatic digital pressure and temperature control, which is the standard sterilization condition for laboratory media. The difference from a pressure cooker is the control system and the automatic shut-off, not the sterilization itself.
How many jars fit in the 25Q?
Up to 14 wide-mouth quart jars standing upright. The chamber is tall and narrow rather than wide, which is what makes that count possible in a 25-quart unit.
Does it need a special electrical outlet?
No. The 25Q runs on a standard 110V household outlet and draws 2kW. No 220V service, no electrician, no dedicated circuit installation required. Give it its own circuit if you can, simply because a 2kW draw on a shared kitchen circuit can trip a breaker.
How long is a full grain jar cycle?
Plan on 90 minutes of hold time at 121°C for grain, plus roughly 25 minutes to reach pressure and cool-down time afterward. Liquid culture and agar media need only 25–30 minutes of hold time.
Can it sterilize spawn bags as well as jars?
Yes, for small-batch work. Bags need to sit so steam can circulate rather than being packed tight. If you are running large volumes of bags every week, a floor-standing commercial autoclave will be a better fit than a benchtop unit.
How does it compare to an All American stovetop sterilizer?
An All American is an excellent piece of equipment and will outlive almost anything. The difference is the workflow. The All American is a stovetop unit you monitor manually for the entire cycle; the 25Q is a self-contained electric unit with its own heating element that reaches pressure faster, holds the setpoint automatically, and shuts itself off. If you want a machine you can load and leave, the 25Q is the one. If you want something with no electronics to ever fail, the All American is.
What maintenance does it need?
Use purified or RO water to prevent scale, keep the lid gasket clean and free of debris, and replace the gasket about once a year, or every six months in heavy daily use. Replacement gaskets are stocked.
- All-in-one, ready to grow
- Produces multiple flushes
- High-quality, USA-made
- Great for home or classroom use
Couldn't load pickup availability
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