Osprey Hydraulics hydration system review

Osprey Hydraulics Hydration Pack

As I was testing the hydration system compatible Osprey Zealot recently, Osprey also sent me one of their Hydraulics hydration systems to test too.  I considered combining it into my Zealot review but, as the Hydraulics system is compatible with many rucksacks, it seemed better to keep it separate.  


The Hydraulics system I tested is 2 litre capacity and comes with everything needed to get up and running.  I have previously used Camelbaks or Platypus models and, while there are lots of similarities across brands, the Hydraulics package is very comprehensive.  The bladder reservoir opens and closes with a dry bag style roll top that is then sealed with a slide across clip.

The bladder is also, interestingly, stiffened in one side.  The hydration tube then exits the bottom of the bladder but has a connector so it is easy to leave that in place on a rucksack and remove the bladder for refilling without unthreading the tube.  

There is a magnetic clip that will connect up to the clip that comes attached to Osprey rucksacks (I’m not sure if this comes as standard on all Osprey packs) and at the end, of course, there is the bite valve.

In Use

I have used the Hydraulics system lots over the last few months.  This has been almost exclusively with an Osprey Zealot biking rucksack although I have linked it up to other packs to see how universal it is. The main activity that I personally use hydration systems for is mountain biking as I prefer just using a bottle in other situations, but the Hydraulics system would work for any sport.

The key things I would want from a hydration system are that they are simple to fill, robust, have an effective bite valve that delivers a good flow and that they are easy to add to my pack.  So, this is the order in which I have considered that Hydraulics system.

As mentioned earlier, all previous hydration systems I have used were filled via a screw top lid on the front of the bladder and this style of slide opening is very new to me.  I must admit I was a little nervous that a system so simple would be fully watertight but I needn’t have worried – I’ve had no sign of leakage at any point.  

The advantage of this system is also that the bladder is very easy to fill.  For me this has always been from a tap but it would certainly be just as easy from a stream.  It also means you can easily add some ice cubes if using it on a hot day.  Having the wide top opening also makes it easy to pour from the bladder into pans or other bottles.

Finally, the large top opening makes it simple to clean the bladder and dry it.  If you leave liquid in the bladder over a period of time mould can build up inside so drying is a good way to avoid this although, as I covered in a top tips article some time ago, I store my hydration bladders in my freezer between uses (please read the top tip here).  Once the liquid is frozen mould growth is inhibited.

The other key aid to easy filling is the solid backplate Osprey have added to one side of the bladder.  This works brilliantly as it gives structure to the unit and this helps with filling but also helps when you are tying to stuff the filled bladder into the back of a rucksack.  It isn’t something I’ve used before, but now I wouldn’t want to be without it.

So the Hydraulics system certainly ticks the boxes for ease of filling, storing and cleaning, but how well does it stand up to wear and tear?  Osprey have used a tough material for the bladder – it has a degree of flex and stretch to it and yet seems very robust.  So far I can certainly say it shows no signs of leakage or wear although I am always careful to ensure it isn’t next to sharp objects in my pack.

The bladder is also quite a streamlined shape and, once it is slid into place in your rucksack,  the next thing to consider is the hose unit.  Osprey have added an inline connector which makes it much simpler to link everything together.  The hose can then be fed round to the front via the shoulder straps and be in position ready for use.  The connector works really well and means the hose can be left in place if the bladder is removed for refilling but I don’t leave the tube in the rucksack for long periods as again mould can start to form.  

At the end of the tube is a magnetic clip to fasten the bladder to the rucksack sternum strap between uses. I wondered if I would find this to be a gimmick but infact it is fantastic.  It clips in securely and keep the bite valve out of the way.  If you are using the Hydraulics reservoir with a different brand of rucksack Osprey conveniently provide a clip and magnet that can be attached to any suitable width strap.  There is a warning in the Hydraulics packaging that, if users wear electronic devices like pacemakers, they must be aware that they have a powerful magnet over the left part of their chest!

The final link in the chain is how well the bite valve and system as a whole deliver liquid.  I have always loved Camelbaks bite valves and did wonder how well I would take to the Osprey one. It is a fairly substantial looking unit that is cleverly angled towards the mouth and to operate users need to bite and suck (no surprise there!).  It actually works brilliantly and delivers a good flow of liquid but shuts off securely as soon as you stop biting.  The bite valve also incorporates a twist cut off valve which is a great addition.  The flow rate is also helped by the 1/4” tubing Osprey use.


This is a great product. It is obviously designed to pair perfectly with Osprey packs and I have found it great with the Zealot I’ve been testing, but have no doubt it will work well with most rucksacks out there.  It is designed for efficiency and durability and delivers perfectly on both counts.  The 2 litre Hydraulics system I’ve been testing retails for £34 and weighs 210 grams.  Highly recommended in every way.  More details are available on the Osprey website here.

Posted by Paul