Hydration Reservoir Buying Guide

Introduction

Hydration packs are an efficient and convenient way of carrying water, helping you stay hydrated in the outdoors.

The key part of a hydration pack system is the water reservoir (sometimes referred to as a bladder) which is connected to a hose and valve that allows you to drink without having to slow down or stop. With developments in design, most modern sport-specific backpacks are now bladder compatible, making a hydration reservoir a worthwhile investment.

Before purchasing a hydration pack/reservoir there are a few key considerations:

What activity you will primarily be using the pack for
Reservoir capacity
Valve system
Additional storage and features

Benefits

Why use a hydration reservoir?

Reservoir types

Material

Typically hydration bladders are made from polyurethane or thermoplastic polyurethane. These are lightweight and durable materials that are thin, but will still last you a long time. Some reservoirs will come with an antimicrobial treatment/technology that helps to inhibit the growth of bacteria on the inside of the bladder.

Shape

The shape of a reservoir plays an important role in the strength and profile of the bladder. In general, the less space the bladder takes up the better. Look for low-profile reservoirs that quite often use a baffled construction in order to keep the size of the bladder as small as possible.

Opening

The opening is key for refilling and cleaning, so is an important aspect to consider.  Some reservoirs offer a wide opening with a screw top. These typically allow enough room for you to fit your hand inside for cleaning and offer plenty of space for quick and easy refilling. They are usually strong and secure bladders. Other reservoirs use a slide/zip-top opening. These bladders open completely at the top which allows for easy cleaning. They are very quick to open and refill, and are a great option if you will be refilling from a moving water source.

Capacity

How to choose reservoir capacity

Making sure that you have the right reservoir capacity is important for staying hydrated for the length of your chosen activity.

Your choice depends on your sport, duration of activity and access to water (for example, the distance between aid station refills at longer running events).

The amount you should drink during exercise depends on several factors, including temperature and workout intensity. As a rough guide, you should look to consume between 0.5 and 0.8 litres per hour of exercise.

0.5 litre capacity is good for shorter running or walking where lightweight is key. You typically won’t find reservoirs this small, so water would usually be carried with a running vest and two small bottles.

1.5 Litres is a good minimalist choice for hikers and runners. Because you are not carrying as much liquid it is nice and lightweight, however, on hot or longer days you will likely need to refill during your activity.

2.5 Litres is a great all-round choice, offering a good balance of weight and liquid quantity. It is a good choice for hiking or longer runs without aid stations.

3 litres or more is suited to longer hiking trips where you aren’t able to refill water regularly or want to minimise stops.

Valve types

What valve types do hydration reservoirs have?

Hydration reservoir accessories

Cleaning

Keeping your hydration bladder clean will make sure that your drink is safe to consume and your reservoir lasts as long as possible. It is especially important to thoroughly clean after any sticky sports/electrolyte drinks are held in your reservoir. Cleaning kits usually comprise of a brush for the main bladder and a brush for the tubing.

Valves

You can change to a bigger or smaller valve, or change to your preferred locking system. It's a useful spare to keep as with heavy use there is a chance you will need to replace your valve. Whilst most bite valves last for years, they will eventually wear out over time.

Insulation kit

Insulation kits allow you to use your hydration pack in freezing temperatures, so are an essential add on for winter users. They usually come in a few parts that cover the reservoir, tube and valve to ensure that your drink doesn’t freeze solid.

Filter

In-line filters are a great and convenient way of helping to ensure your water is safe to drink. They replace your tubing and valve to filter your water as you drink - a must-have for remote trips when you may be refilling from natural water sources.

Tube routing

This is the slit/hole which allows you to route the tube from your hydration pack from the reservoir out of your pack/vest. Some packs will have more than one opening for this, allowing the tube to sit on either shoulder, whereas others will just have a single route. Occasionally packs with one route will have this set to one side, but typically it is central, allowing the user to decide which shoulder the tube will follow.

Quick release tube

For ultimate convivence when refilling the bladder, some reservoirs come with a quick-release tube system that allows you to disconnect the tube from the reservoir, leaving it in place on your pack whilst removing the bladder. This is especially useful for packs where the tube is routed.

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