Buyers' Guide - Hydration Systems

Bladders come in all shapes and forms, the most common capacities are two litres and three litres. We'd suggest that you go for the larger variation, after all you don't have to fill it all, but in hot weather, one litre per hour isn't out of the question.

When it comes to choosing an actual bladder, things get more complicated. Despite what manufacturers tell you, most bladders will end up tainted in taste terms if you regularly use sport drinks and most will, eventually, die after extended service.

In day to day use, a useful feature is some sort of anti-microbial treatment which will delay the time it takes for mould to grow in an unattended system - both Camelbak and Source plus some others feature this. Deuter use the Source bladder by the way.

Different companies use different materials for the bladder, Platypus, for example favours beverage-grade polyethylene, Source uses a PE film to minimise plasticy tastes while Camelbak now has a lifte-time guarantee on its bladders. We like the Source version for its ease of cleaning and minimal tainting.

The opening method of the bladder is the other big consideration. We've found threaded caps like the ones on the Camelbak Omega and some others can become sticky, especially if energy drink gets on the threads. A really big opening like the simple fold-over and clip version on the Source Widepac or Platypus's Big Hoser bags is easier to use and makes cleaning acccess to the bag simpler. Tip A smear of vaseline can help keep sticky lid threads smoother running.

With a bite valve, you're looking for two things - good flow rates and simplicity. The best we've ever used is still the Camelbak Big Bite valve. It's simple, doesn't leak and flows like a dream. We even pop them onto other brands' hydration packs if we prefer the bladder.

Mechanical-type valves with springs and hard innards are all very well, but seem more prone to failure, contamination and simply don't flow as well, though most will be adequate.

A lock-out facility means your hydration system is less likely to spill its innards in the back of your car, but you still need to remember to switch it on... Again, we like the Camelbak version.

Finally, a right-angled, ergonomic valve will put the mouthpiece at a more user-friendly angle. You guessed it, we like the Camelbak one here too.

Without getting into an endless debate, we'd tend to buy the pack for the job then add a decent hydration system to it rather than buying all in one, unless we were getting a very good deal and were after a small-capacity biking or running pack.

Most purpose-built hydration packs aren't large enough for general use, though we like the TNF series which come complete with decent Nalgene bladders and, for a stand-alone, the amusingly named Berghaus Bladdered, though the latter is supplied without a sytem.

Generally look for a decent-sized hydration sleeve - especially if you have a three-litre bladder - with a hook or straps at the top to hold the top of the bladder. Check how easy it is to route the hydration tube out of the pack and whether you can use either side, or there's a central opening. Finally, the shoulder straps should have some retainers to stop the tube from flapping around - we like the Osprey ones that angle things neatly into the right place.

New users are often bemused by caring for their packs, but in reality it's quite easy. Rinse straight after use and either store in a freezer or dry carefully and store open and dry.

If you do get mould growth, you have a number of options. We'd suggest you invest in a set of specialist brushes that will enable you to clean the tube thoroughly, rinse afterwards with warm soapy water then dry out as before. In bad cases, use the sterilising fluid sold to rinse babie's bottles and soak overnight.

Camelbak also sells sterilising tablets or some users swear by denture cleaning tablets. If you have a bad attack of mould, dismantle and thoroughtly clean the bite valve as well. The alternative is generally agippy tummy, which is the last thing you want on the hill.

You can buy neat little insulated tube and bite valve covers, but in our experience, once the going gets cold, they have only a minimal effect. Blowing back fluid into the bladder after drinking helps to prevent the tube from freezing solid - it always go first - and starting off with warm water in the first place will also help.

When you get well below zero however, things will tend to freeze. We've had an enture bladder go solid in the Andes before now....

More Help and Advice

This article should have given you some basic pointers. The good news is that there's a load more advice on OUTDOORSmagic:

• Ask on the gear forum about general issues or specific items.
  
• Check the member reviews section for user experiences of kit.
  
• See OM editorial reviews on the front of the site for our impressions.
  
• Ask Richard Gear if you have a specific question you need answering.