FAQs, Tips, Tricks & Bizarre Stuff

Sure can! Here's a link to a copy of those simple instructions we included on the hangtag of your Rumble Jar. Feel free to print it out a thousand times to make some avant garde wallpaper.

Have a look at this link: detailed instructions page

We even threw in some gifs free of charge!

Whoa, take it easy over there! Quite frankly, you can do whatever you like, but we wouldn't recommend over-shaking. In general, the "Rumbling" step (i.e. agitation) is just intended to soak all the grounds in water. Over-agitating definitely won't make better coffee, but it definitely will make more silt/sediment! 

To watch proper rumbling in action, have a look at "Step 2: Get your rumble on" in our Brewing Instructions page

And if you're using fine grounds, you may want to add a couple more rumbles if you're noticing the dry grounds issue (see related FAQ).

We've seen this happen a few times with certain well-known and very-affordable brands of pre-ground coffee. After brewing, you might notice some of the grounds in the center of the filter still appear dry. Well, that's because they are in fact stuilldry! If you use the kinds of beans mentioned above and notice this happening to you, here are a few fixes for your next batch (try them individually, in this order):

1) Fill up water level so it covers the cap. Coffee grounds float, so this ensures the grounds will be under water while they're contained within the filter. 

2) Use a total of 4 "rumbles" rather than the recommended 2 rumbles ("rumbles" are the standard end-over-end vertical shakes depicted in step 2 of our instructions).

3) If the 2 additional rumbles don't do the trick to soak all the grounds work, try giving it two horizontal shakes on your next batch. This loosens up the grounds that might be caked to the wall of the filter and plugging up the holes so water can't circulate. Don't overdo this step though...too much of it can create a lot of sediment.

4) Consider using coarse grounds. They're recommended by the cold brew experts anyway, and we've never seen dry grounds occur when brewing with coarse ones.

If you're steeping in a refrigerator: 16-24 hours. 
If you're steeping at room temperature: 8-12 hours.

While not strictly necessary, coarser-ground coffee is preferred instead of finer-ground coffee for two reasons: 1) coarse grounds result in far fewer particles (aka "silt" or "sediment") winding up in the drinkable brew, and 2) finer grounds have a tendency to "over-extract" (a fancy term describing a brew that's overly bitter and pungent). If you're familiar with the ground size typically used in a French Press, Chemex, dripper or percolator, you can basically just use that same size. 

You can still make cold brew just fine if you're using fine grounds in your Rumble Jar though. If you're OK with a little more silt in the bottom of the jar or a bit more tangy flavor, it works perfectly well. Plus, Rumble Jars do come nestled in a 100% cotton bag that doubles as an optional second-stage filter for folks sensitive to the silt left over from the finer grounds. The second-stage filter does a phenomenal job at filtering out the excess particles, but it's an added step that could be a bit overkill for the average person and totally unnecessary if you use coarse grounds.

Nope! It's entirely up to you which type of coffee you use in cold brew. The one caveat is that it's better to use coarse grounds instead of finer grounds. We do recommend experimenting with a few different roasts or flavors though, because cold brew tastes quite a bit different than your typical hot coffee. We've heard reports of folks discovering a preference for darker roasts for their cold brew, since that adds a bit more strength to counteract cold brew's sweeter flavor and lack of acidity.

"It depends" is a lame answer, but it definitely does apply here. Being prescriptive about the correct coffee-to-water ratio is impossible (and anyone telling you they know the answer is just making it up!). It's highly dependent on your ingredients (beans, how they're ground, roasting method, etc.), the brew method (time, fridge vs room temp, type of water, etc.) and most importantly your individual taste preference. So if you Google it, you'll see an incredibly wide array of opinions about the correct ratio. 

So our best advice is to use your Rumble Jar to figure it out yourself. We've included those two notches (i.e. those short horizontal lines) in the metal filter as guides, not as prescriptive tools. They're there to help you eyeball your grounds as you prepare a batch and roughly figure out how much you personally prefer. We've found that the vast majority of cold brew drinkers prefer to fill up the filter with grounds somewhere in between those two notches. Here's a close-up pic of the two notches.

The lower notch is our best guess for where you'll want to start (~1.5 ounces of ground coffee in the quart size and ~3 ounces in the half gallon size). Fill your grouds to that line, drink a batch of cold brew and then reassess to figure out whether you want more grounds for your next batch.

The higher notch holds ~3 ounces of grounds in the quart size and ~5 ounces in the half gallon size. Some folks like to brew a higher-strength concentrate and then dilute it with water/milk/ice when they drink it, so that's an option too if you want to get more cups out of a single batch of cold brew.

The quart size Mason jar comes in two different versions, and the only difference is in the exterior design. The New & Sleek jar has the same dimensions, strength and seal as the Traditional one, but it just contains fewer decorative elements on its exterior. So the glass has a cleaner, smoother look and gives a better view of our filter on the inside. But the downside is that the New & Sleek jar does not contain the built-in measurement lines that are normally imprinted on the side of the Traditional Mason jar. If you value having those built-in measurements, the Traditional jar will be better, but if you want a smoother-looking jar, the New & Sleek one will be better.

By weight (quart size / half gallon size respectively)

Filled to the Lower Notch: ~1.5 ounces of ground coffee (quart size) / ~3 ounces (half gallon size)
Filled to the Upper Notch: ~3 ounces / ~5 ounces
Maximum: roughly 4 ounces / ~7 ounces 

By volume (quart size / half gallon size respectively)

Filled to the Lower Notch: ~half cup (~120 mL)* / ~1 cup (~240 mL)*
Filled to the Upper Notch: ~1 cup (~240 mL)* / ~ 1.5 cups (~360 mL)*
Maximum: roughly ~1.3 cups (~320 mL)* / ~2.3 cups (~560 mL)*

*For more on the insanity of using "cup" as a measurement tool, have a look at our Bizarre stuff section below.

Cold brew can be stored up to two weeks in your fridge (as long as the grounds have been removed). That's part of the reason we designed our filter to work in tandem with the world's best storage container: the Mason jar. Those time-tested, leakproof, airtight seals will keep your coffee fresh for a while. So don't worry about brewing too much coffee or even a batch of concentrate to use throughout the week. Just make sure the grounds don't steep for longer than 24 hours, or else it could taste a little funky.

We intentionally designed our Rumble Jar filters to work with Mason jars because 1) they're the best drinking/brewing/storage vessels ever made, and 2) they're easy and affordable to replace in case you lose or break it. Cheap and awesome is a combo we love! 

The Mason jars that are compatible with our Rumble Jar filters are among the most widely available versions you can find (and they're also very affordable!). 

Quart-size (32oz) Rumble Jars

Our original, quart-size Rumble Jars already come with a totally-standard wide-mouth Mason jar. But in case you need a replacement Mason jar, the key things to look for are WIDE MOUTH (i.e. not regular mouth) and STANDARD (i.e. not the more obscure shapes/sizes). 

Half-Gallon Rumble Jars (filter-only)

Our half-gallon (64oz) Rumble Jar filters don't include a Mason jar. In addition to these jars being super expensive to ship individually, tons of folks have told us they already have one at home they can use. You can usually buy a dozen in a store for about the same cost as buying just one online (so chalk up a win for brick-and-mortar!). That's the reason we go filter-only for this half-gallon size. The other really nice thing about the half-gallon size is that there is really just one standard mouth size, so you don't have to worry about the wide-mouth vs. regular-mouth distinction like you do with the quart-size jars. With half-gallon jars, they're essentially all wide-mouth (except for a rogue "Extra Wide Mouth" decorative jar that we're fairly confident you don't own and wouldn't be tempted to use for coffee anyway).

As always, feel free to send us an email in case you have a question about a particular Mason jar model, and we'll be happy to steer you in the right direction. 

First, thanks for calling our filters "amazing"! We do offer the filter+cap separately on the half-gallon version only. That's because the half-gallon jars cost a fortune to ship, and unlike the quart size jars which commonly come in two different mouth sizes (regular and wide), the half-gallon version only comes in the wide-mouth size. So there's basically no risk of you buying an incompatible half gallon Mason jar, and a lot of folks already have one at home that will work just fine!

Yes.

Yes. Plus the cap comes in your choice of color. Check out photos of the different options towards the bottom of the product page.

When you receive your Rumble Jar, you'll find it nestled comfortably inside of a 100% cotton filter-bag. Hang onto that bag! It functions as a pretty fantastic (and totally-optional) "second-stage" filter.

How do I use the filter-bag? It's really only useful if you're forced to make cold brew with fine grounds (remember: coarse grounds are recommended for making cold brew). Once you've brewed a batch of cold brew with fine grounds and removed the filter+cap from your Rumble Jar, you can add an optional step where you use the filter-bag to strain your batch of cold brew a second time to remove additional silt/sediment and produce a clearer-looking brew. Have a look at our FAQ about using coarse grounds and our FAQ about silt for more on that topic.

Isn't this extra filtering step time-consuming and anti-Rumble Jar simplicity? Perhaps...and that's why it's completely optional and only suggested for folks brewing with fine grounds. This extra filter may be helpful if you only have finely-ground coffee available, since that tends to produce more silt/sediment than the coarse grounds recommended for cold brew. 

Personally, we don't use the second-stage filter because we brew with the recommended coarse grounds, and we've grown accustomed to a little bit of sediment that's characteristic of cold brew. But if you use finer grounds and want a surefire way to get rid of extra sediment, give that secondary filter a go! And if you have no need for a second-stage filter, you can always repurpose it as a bag for like, storing stuff.

How do I clean the filter-bag?  Have a look at our cleaning instructions section.

Most filters have holes in the bottom that match the holes in their walls. Instead, we designed the bottom of the Rumble Jar filter to feature a hole-free dish that we call a "silt pan" (have a look at the close-up photo here). When you're removing the filter from the jar, that silt pan collects some of the excess sediment and prevents it from draining into your drinkable brew. If there were holes in the bottom, that sediment would immediately drain out into your coffee. Our silt pan certainly doesn't capture all of the silt/sediment, but we were definitely able to notice a difference.

Sure can! Just shoot us a note via our Contact page (or scroll to the bottom of this page for a Contact link) and please include your order number to get started.

Rumble Jars are:

• Designed and assembled in USA. 
  
• The Mason jar itself, the packaging and the tags are made in USA. 
  
• The filter and cap are made in Taiwan. 
  
• The cotton secondary filter-bag is made in China. 
  

A lot of folks find it just plain-old tastes better. The secret is that cold water extracts ~70% less acid from the coffee grounds than hot water (plus it also pulls out fewer alkaline solubles), which means that your coffee ends up tasting a lot less sour and bitter. 

So if you're new to cold brew, get ready to enjoy a smoother, sweeter flavor of coffee.

Only the good stuff! Unfortunately if you removed all silt (aka "sediment") from cold brew coffee, you wouldn't have all that much coffee left over...and what you did have left over wouldn't taste all that good! The silt is caused by tiny coffee particles sneaking through the holes in the filter. These particles are also found in traditional hot-brewed coffee, but you just don't notice them as much because the heat disperses the particles throughout the cup. They're still there, but you just end up drinking them. Cold brew's long-steeping process results in this silt sinking to the bottom. We've been warned by our cold brew expert advisors Jittery John's that silt is a natural feature of cold brew coffee, and if you eliminated all of it, you wouldn't like the result!

If you're used to drinking hot coffee (and particularly if you prefer strong, dark roasts), there's no question cold brew will taste different. It should taste lighter, sweeter and more balanced, but it should not taste watery. If you're finding it tastes watery, the best solutions are to increase your steeping time to a full 24 hours, ensure all grounds in the filter are initially wet, and potentially use a darker type of bean. Regardless, it will be impossible to replicate the more bitter and acidic taste of traditional coffee, so if that's what you're craving, hot coffee might be right for you.

We have no idea.  

Yes. You can clean all components (excluding the cotton bag) in a dishwasher or by hand.

First, we typically dump out as many grouds as possible into the trash/compost (side note: try this gardening trick!). A couple quick upside-down vertical shakes and that's that. Then we typically rinse the grounds off the walls of the filter by running the faucet along the outer walls of the filter. Then, we run the faucet inside the filter, and what you'll notice is that a pool of water will collect in the bottom before it quickly drains out through the walls. So we basically take advantage of this temporary pooling effect by doing a series of rapid fill-and-swirl-then-dump-upside-down maneuvers one after the other. We personally don't mind a couple stray grounds left in our filter, but if you do enough of these maneuvers, you can definitely get all of them out! 

Rinsing thoroughly with water and air-drying is probably the most used option, but for a more thorough clean you would put them in a washing machine (but air dry or else they'll shrink and get warped). We don't recommend putting them in a dishwasher, but that's also an option. Anyway, cleaning these things properly can be a bit of a chore, which is another reason we don't love using them!

Unless noted otherwise, we use USPS for all shipments, domestic and international.

We typically ship out orders same-day or by the next business day.

Domestic: For the vast majority of the US, shipping will take 1-2 business days from when it's shipped until it's delivered to you. More remote US locations might see this timing stretched to 3-4 business days. 

International: We send packages via USPS' Priority International service, and they quote 6-10 business days for delivery. Keep in mind that customs delays can happen and also that the package will be handed off to your local mail carrier for final delivery, so those issues can occasionally extend the timing beyond 10 days. In our experience though, Priority International has done a great job of delivering the vast majority of customers' packages quicker than 10 business days.

Because so many folks from abroad were awesome about asking us for Rumble Jars, we now offer international shipping to a whole host of countries. If shipping isn't available to your country, please send us a message and we will look into the policies and costs and let you know if we can add it. 

IMPORTANT: Our international shipping costs do not include customs fees or taxes. Sorry about that! So, just make sure you take into account any additional fees and taxes charged by customs in your country, as well as for ensuring the imported product complies with your local laws. Thanks for your understanding!

Of course! Cold brew makes for an excellent iced coffee, and it's super easy to make with a Rumble Jar. Just brew a batch normally in your Rumble Jar, but make sure to use more grounds in the filter than you normally would. Consider filling up the filter to the Concentrate Notch. The reason is that once you pour your brew over ice, the ice starts to melt and dilute your coffee, so starting with a a stronger concentrate will counteract any watery taste.

Nope. Iced coffee generally refers to a standard drip hot brew which is then poured over ice to cool it down. Since the coffee is originally brewed with hot water instead of cold, it's more acidic and tends to have a more bitter taste.

There's good news for you, but you'll have to enter our Secrets & Tricks portal to learn about this secret/trick.  

You can indeed make cold brew and then heat it up. It won't suddenly turn bitter and lose its sweeter flavor. That's because the acidic compounds reside in the coffee grounds, so once they're removed (and please don't forget to remove those grounds before heating!), you can prepare your coffee any way you like. So go heat it up and add whatever else you normally would to your hot coffee. Our bet is you'll find yourself needing less sweetener than you did before. 

Take those coffee grounds and make a greener garden.

The cup is an official measurement of insanity. For more on why, we turn to this HuffPo article or this Wiki article about all the varying definitions of one cup. And going forward let's never refer to a "cup" as a measurement again.

Although masonry professionals are tehcnically still allowed to use them, Mason jars actually get their name from their 19th century inventor, a fellow named John Landis Mason. More about him and the riveting history of Mason jars can be found on this Wikipedia page. You might need a full Rumble Jar in order to read the article in its entirety.