By Caleb MorganThe fastferment conical fermenter 7.9 gallon is a good fit for homebrewers who want a closed, stackable vessel that lets them harvest yeast and drop trub without moving to stainless steel. It suits 5-gallon batch brewers working with kits or all-grain recipes who are ready to move past the bucket. It is a weaker choice for people who plan to brew big 10-gallon batches, need a fully pressure-rated vessel for lagers under heavy carbonation, or want a unit with a built-in cooling jacket. Before you buy, check your batch size, your temperature control setup and how you plan to clean and transfer, because those factors decide whether this fermenter earns its shelf space.
Product Overview
The FastFerment is a conical fermenter made from food-grade plastic, sold in a 7.9 gallon capacity. The conical bottom is designed to collect yeast and trub at a single point, so you can drain clear beer from a sanitary valve above the sediment layer. Most owners use it for 5-gallon batches, which leaves comfortable headspace for active fermentation. The unit includes a lid with a gasket, an airlock port and a drain valve on the cone. Its shape and lid design have made it a common choice among homebrewers who came up through plastic buckets and want a more controlled setup.
The design targets a middle ground between a basic plastic bucket and a stainless conical. You get many of the practical benefits of conical fermentation, such as easier yeast harvesting and cleaner transfers, at a price point that suits budget-minded brewers. The trade-off is that plastic is more scratch-prone than steel and does not hold up to the same aggressive cleaning chemicals, so care during cleaning matters.
Key Features & Specifications
The table below lists the characteristics that are consistently described in product information and owner discussions. Confirm exact dimensions and fittings against the packaging or manufacturer listing before you order, since specifications can vary between production runs.
| Feature | What It Means for Brewers |
|---|---|
| Nominal capacity: 7.9 gallons | Sized for 5-gallon batches with room for krausen |
| Conical bottom | Collects trub and yeast at the cone for separation |
| Sanitary drain valve on cone | Lets you drain clear beer or harvest yeast from the base |
| Airlock-compatible lid | Standard grommet and airlock setup for closed fermentation |
| Food-grade plastic construction | Lighter than steel and less fragile than glass |
| Stackable form factor | Can be stored and handled in tight brewing spaces |
If you plan to use a temperature controller or fermentation chamber, measure the interior diameter and height against your chamber before buying. Conical fermenters take up more vertical space than buckets, and some chamber shelves will not accommodate the cone.
Pros & Cons
Pros
- Conical design makes yeast harvesting and trub removal simpler than with a flat-bottom bucket.
- The drain valve on the cone allows transfers without disturbing sediment.
- Lighter than stainless steel and easier to move between shelves or rooms.
- Works well with standard airlock and bung setups that most brewers already own.
- A budget-friendly route into conical fermentation for home brewers.
Cons
- Plastic scratches more easily than stainless, which can harbor bacteria if cleaned poorly.
- Not designed for high-pressure carbonation or serious lagering under pressure.
- Some owners report that the cone valve needs careful tightening to avoid leaks.
- Capacity is best suited to 5-gallon batches; it is not a 10-gallon solution.
- No built-in temperature control, so you will need a separate setup for temperature management.
Performance Analysis
Based on the specifications and recurring themes in owner feedback, the FastFerment performs best in a predictable, moderate-temperature environment. Ale fermentations between 62 and 72 degrees Fahrenheit are the most commonly described use cases, and the conical shape helps yeast settle into a compact cake. Owners who harvest yeast from the cone typically report that the sediment layer is easier to isolate than in a bucket, though you should still expect some loss of clean yeast if you wait too long or pull too much.
Headspace is an important factor. A 5-gallon batch in a 7.9 gallon vessel leaves a reasonable margin for vigorous krausen, which reduces the chance of blowoff. Brewers using high-gravity recipes should measure expected foam volume before pitching, since a heavy fermentation can still fill the headspace quickly.
Sealing and cleaning are the two areas where owners most often describe frustration. The lid gasket needs to sit flat for a good seal, and the drain valve should be checked for tightness before each batch. Plastic does not tolerate abrasive scrubbing well, so soft brushes and no-rinse sanitizers are the usual recommendation. Keeping the cone free of dried trub makes the valve easier to operate and reduces the risk of contamination.
Carbonation and cold crashing are less straightforward. Because plastic is not a pressure vessel, many brewers transfer to a keg or bottling bucket for carbonation. Cold crashing in a fridge or chamber is possible, but you should monitor the lid and valve for condensation and leaks.
Who Should Buy This Product?
This fermenter fits brewers who regularly make 5-gallon batches and want to add conical fermentation without a large investment. It is especially useful for people who harvest yeast for reuse, since the cone concentrates the yeast cake. Brewers who already use buckets and want a cleaner transfer route will also find the valve a practical upgrade.
You should skip this fermenter if you brew 10-gallon batches, plan to carbonate in the vessel under pressure, or want a stainless unit that will last decades with aggressive cleaning. Brewers who need a built-in cooling jacket or precise temperature control built into the vessel may also prefer a different product.
Buying Guide
When you evaluate a conical fermenter, start with batch size. Most 5-gallon recipes need a vessel of roughly 6.5 to 8 gallons to leave headspace, so the 7.9 gallon capacity is a sensible match. Next, consider material. Food-grade plastic is light and forgiving to handle, while stainless steel is more durable and more tolerant of sanitizers and heat. Glass is inert but fragile, so it is less common for conical designs.
Check the valve and the lid before buying. A drain valve that is hard to tighten or a lid without a good gasket will cause problems in use. Confirm that the lid accepts a standard three-piece airlock and a temperature probe grommet if you plan to monitor fermentation. Also measure your fermentation space: the cone adds height, and many chest freezers or fermentation chambers have limited interior room.
For a broader view of your options, see Best Homebrew Fermenters: 5 Plastic, Glass and Steel Options, which compares several materials and styles.
Well-known alternatives include the following:
- Speidel Fermenter: A German-made plastic conical with a long track record among homebrewers. Many owners prefer its sturdy build for repeated use. View on Amazon
- Brewer’s Best Conical Fermenter: A plastic conical option aimed at beginners, often chosen for its straightforward design. View on Amazon
- Chapman Conical Fermenter: A stainless-style conical that appeals to brewers who want a more durable, long-term vessel. View on Amazon
Each alternative has its own strengths in durability, cleaning and fit for your space, so compare them against your batch size and brewing goals before you decide.
FAQ
Is the FastFerment conical fermenter 7.9 gallon suitable for 5-gallon batches?
Yes. A 5-gallon batch leaves comfortable headspace in a 7.9 gallon vessel, which is why it is a common size for home brewers. Leave room for vigorous krausen if you brew high-gravity beers.
Can I use the cone valve to harvest yeast?
Many brewers use the cone valve to collect the yeast cake after fermentation. Drain the trub first, then open the valve slowly. Harvest soon after fermentation finishes, since yeast viability declines over time.
Is this fermenter pressure-rated for carbonation?
Plastic conical fermenters of this type are generally not designed as pressure vessels. Most brewers transfer to a keg or bottling bucket for carbonation. Check the manufacturer’s guidance before pressurizing.
How should I clean the plastic to avoid scratches?
Use a soft brush or sponge, avoid abrasive pads, and rinse thoroughly. A no-rinse sanitizer after cleaning helps. Replace the vessel if deep scratches develop, since they can harbor bacteria.
Can I cold crash in this fermenter?
Cold crashing is possible in a refrigerator or chamber, but monitor the lid and valve for condensation. Make sure the vessel fits the cold space before you commit to the process.
Does it include a temperature control?
No. You will need a separate temperature controller, heating belt or chamber setup to hold fermentation temperatures steady.
Is it a good choice for beginners?
It can be, especially for brewers who want to learn conical fermentation without a large commitment. Beginners should practice leak checks and sanitation before each batch.
Final Verdict
The fastferment conical fermenter 7.9 gallon is a practical, budget-minded choice for 5-gallon homebrewers who want the yeast harvesting and trub separation benefits of a cone. It is best for ale brewers working in controlled temperatures who are comfortable with careful plastic cleaning. It is less suitable for pressure carbonation, 10-gallon batches or long-term heavy use. If your setup matches those strengths, it is a sensible step up from a bucket. You can find it here: View on Amazon.
About Caleb Morgan
Caleb Morgan is part of our editorial team and reviews and edits our home brewing guides, checking product details against manufacturer specifications and owner feedback.
