You can easily cut the tube of the water bladder to your preferred length!
To do this, remove the bite valve, put the tube in some hot water to soften it, cut it to the required length and replace the bite valve.
The bite valve has an on/off closure system to prevent leaks during transportation. When running, it does not leak, even when it is in the open position. In order to get a good flow rate when you drink, pinch the bite valve with your mouth and suck!