How to Hydrate on the Go: Using the Hydrapak 3.1L OHY Diagonal Port Reservoir
By MYSTERY RANCH Backpacks | Built for the Mission | Published: 2026-08-16
Category: How-to Guides
Learn how to set up, use, and maintain the Hydrapak 3.1L OHY Diagonal Port Reservoir. Get hydration tips for hiking and outdoor adventures with Mystery Ranch packs.
Staying hydrated is essential for any outdoor adventure, whether you're hiking a rugged trail, working a long shift, or exploring the backcountry. Carrying enough water can be a challenge, but a hydration reservoir system makes it easy to sip on the go without stopping to dig out a bottle. The Hydrapak 3.1L OHY Diagonal Port Reservoir, designed to integrate seamlessly with Mystery Ranch packs, offers a convenient and reliable solution.

In this guide, we'll walk you through everything you need to know about using the Hydrapak 3.1L OHY Diagonal Port Reservoir. From initial setup and installation to cleaning and maintenance, you'll learn how to get the most out of this hydration system. Whether you're a seasoned hiker or new to using reservoirs, these tips will help you stay hydrated and focused on your mission.
Getting to Know the Hydrapak 3.1L OHY Diagonal Port Reservoir
The Hydrapak 3.1L OHY Diagonal Port Reservoir is a high-capacity hydration bladder designed to fit into compatible Mystery Ranch packs, such as the Women's Metcalf 75 Pack or The Brain. Its diagonal port placement allows for easy access and routing of the drinking tube, making it a popular choice for hikers and outdoor enthusiasts. The reservoir holds 3.1 liters of water, providing ample hydration for long treks.
The reservoir features a durable, BPA-free construction and a wide-mouth opening for easy filling and cleaning. The hose is equipped with a bite valve that delivers water on demand, and the Quick Connect system allows you to detach the hose from the bladder for convenient refilling without removing the entire reservoir from your pack.
- The 3.1L capacity is ideal for all-day hikes or extended activities.
- The diagonal port design ensures the hose routes comfortably over your shoulder.
- The Quick Connect system lets you detach the hose for easy refilling.
How to Set Up Your Hydrapak Reservoir
Before you hit the trail, you'll need to install the reservoir in your pack. First, open the reservoir's wide-mouth cap and fill it with water. Avoid overfilling; leave a little air to allow for expansion when the water freezes or sloshes. Then, securely close the cap and check for leaks by turning it upside down briefly.
Next, locate the hydration sleeve in your Mystery Ranch pack. Most packs have a dedicated compartment designed to hold a reservoir. Slide the filled reservoir into the sleeve, ensuring the hose exits through the designated port. Route the hose through the shoulder strap clips and adjust the bite valve to a comfortable position within easy reach.
- Always clean the reservoir before first use to remove any manufacturing residue.
- Route the hose over your shoulder to prevent it from snagging on branches.
- Use the magnetic clip (if included) to keep the bite valve accessible and secure.
Tips for Using Your Reservoir on the Trail
Using a hydration reservoir is simple, but a few tips can enhance your experience. First, practice using the bite valve before your trip. Bite down gently and suck to release water; release the bite to stop the flow. This takes a little getting used to, but it becomes second nature quickly.
Monitor your water intake. With a 3.1L reservoir, you have plenty of water, but it's easy to forget to drink. Set a reminder to take a sip every 15-20 minutes, especially in hot weather or during strenuous activity. Also, consider adding electrolyte tablets to your water to replace minerals lost through sweat.
- Keep the bite valve clean by covering it with the dust cap when not in use.
- If the water tastes like plastic, rinse the reservoir with a baking soda solution.
- For cold weather, blow air back into the tube after drinking to prevent freezing.
Cleaning and Maintaining Your Hydrapak Reservoir
Proper cleaning is crucial to prevent mold and bacteria growth. After each use, empty the reservoir and rinse it with warm water. Use the cleaning kit (sold separately) to scrub the inside and the hose. For a deeper clean, use a solution of water and mild soap or a specialized cleaning tablet. Avoid using harsh chemicals or abrasive brushes that could damage the reservoir.
To dry the reservoir, hang it upside down with the cap open and the hose disconnected. Ensure it is completely dry before storing to prevent mold. Store the reservoir in a cool, dry place away from direct sunlight, and avoid folding it in a way that could crease the material.
- Clean the reservoir after every use, especially if you've filled it with sports drinks.
- Use a drying rack or hang the reservoir upside down to ensure thorough drying.
- Inspect the hose and bite valve regularly for wear and replace if damaged.
The Hydrapak 3.1L OHY Diagonal Port Reservoir is a reliable hydration solution for any outdoor adventure. By following these setup and maintenance tips, you can ensure a steady supply of water and a comfortable experience on the trail. Pair it with a compatible Mystery Ranch pack like the Women's Metcalf 75 Pack to maximize your carrying comfort and hydration efficiency. Stay hydrated, stay safe, and enjoy your time outdoors!



