Cold brew works best with coarse ground coffee, though medium grind is also effective. Coarse grind (like sea salt) enables faster filtration; medium grind (like sand) can enhance flavor and increase yield but may contain fine powder that slows filtering. Avoid fine ground coffee, as it clogs filters.

Start with 8oz of coffee in a 64oz mason jar, then fill with water. The mixture should sit at least 1 inch below the rim after water absorption. This creates strong concentrate that dilutes to taste at ratios from 1:1 to 1:2.

Yes, most store-bought coffee is medium grind and works with JARVA's pressure filtration. Coarse ground isn't commonly available in stores but can be ordered online or requested from local roasters. Results vary by brand.

Steep for 12 to 24 hours at room temperature or refrigerated. A 12-hour steep yields lighter flavor; 24-hour produces stronger concentrate. Medium grind benefits from shorter steeping times.

Modify the coffee-to-water ratio during brewing or adjust dilution after filtering. Use more coffee for stronger concentrate, or increase water for weaker. Dilute concentrate to taste after filtration.

Yes, steep loose-leaf tea for 8 to 12 hours, then filter to create smooth, less acidic tea concentrate. Popular options include hibiscus, yerba mate, and herbal teas. Avoid fine powders that clog filters.

Medium to dark roast coffee beans work best due to bold flavors and lower acidity. Medium roasts offer balanced flavor with sweetness; dark roasts provide chocolatey notes and a smooth profile. Latin American beans deliver chocolate and nut flavors; Indonesian beans offer earthy undertones; African beans provide fruity, citrus notes. Single-origin beans highlight regional characteristics; blends provide consistency. Popular choices include Colombian Supremo, Brazilian Santos, Sumatra Mandheling, Ethiopian Yirgacheffe, and Guatemala Antigua.

Concentrate lasts up to two weeks in an airtight container. Best consumed within 7 to 10 days for optimal freshness. Can be frozen to extend shelf life.

JARVA uses pressure-based filtration, creating low pressure in the top jar to move coffee through multiple micro-fine filters into the bottom jar in about 60 seconds. This prevents clogs and delivers cleaner concentrate than gravity-based systems.

JARVA requires 64oz Ball® wide-mouth mason jars with a mouth opening of 3.38 inches (86 mm) in diameter. We cannot guarantee fit with non-Ball® jars, as this affects filtration efficiency and pressure.

Fine coffee grounds likely clog the filters. Turn off the system, make sure the cone and disc filters are properly positioned, and check for fine powder in medium grind coffee. Try filtering without the paper filter, and clean the filters and air straw thoroughly.

No, JARVA is not designed for hot coffee or hot liquids.

The system is currently available exclusively on our website.

Shipping is limited to the United States. For international inquiries, contact us directly. Mason jars cannot ship to Hawaii or Alaska.

Returns and exchanges are allowed within 30 days of shipment for unused, unopened products. Full details appear in our Shipping & Returns Policy.

Yes, free shipping is available within the continental United States on orders over $50, excluding Hawaii and Alaska.

Orders process within 1-2 business days, then allow 2-5 days for U.S. delivery. Tracking numbers are provided after shipment.

Send a photo of the damaged item within 48 hours of delivery to hello@jarva.co and we'll arrange a prompt replacement.

Make sure you're using 64oz Ball® wide-mouth mason jars. Check that the silicone gasket is properly positioned and undamaged. Wipe the jar rim to remove grounds that prevent sealing, and tighten the connection firmly. Inspect the gasket for wear if leaking continues.

Verify the power adapter is fully inserted and the outlet works. Look for water in the air pump or power socket, and if found, unplug immediately and dry thoroughly. Examine the power cord for damage. Contact support if it still won't power on.

Fine grounds likely clog the filters. Use coarse or medium grind, try removing the paper filter, and clean the cone filter, disc filter, and air straw. Shake the mixture before filtering to prevent compacted grounds. Contact support if slowness persists.

For weak coffee: increase the coffee-to-water ratio, extend steeping to 24 hours, or use a medium-to-coarse grind. For bitter coffee: shorten the steeping time, use a coarser grind, or switch to fresh beans.

Turn off and unplug the system. Use the straw cleaning tool to gently press the drainage hole and release excess pressure. Remove the cone and disc filters, then rinse thoroughly from the opposite filtration direction. Avoid fine or powdery coffee in the future.

Use the straw cleaning tool in the drainage hole to release pressure buildup. If there's no pressure, the system may be overtightened, so apply firm, even unscrewing pressure. Avoid overtightening and use a medium-to-coarse grind to prevent future clogging.

The main JARVA device is not dishwasher safe and should not be submerged. The stainless steel filters and one-way air straw are dishwasher safe.

Replacement filters and parts are available in our shop, or contact us and we'll help you find what you need.

Email hello@jarva.co or call (619) 431-0168. You'll reach the people who actually built JARVA.