How to clean running soft flasks and reservoirs

You have finished the run, taken your shoes off and probably want a shower and something to eat. Getting the flask out of your vest now makes the next outing easier: empty it, clean the drinking parts as well as the container, and give everything room to dry. That small routine beats finding yesterday’s drink still sealed inside when you are trying to get out of the door.

Give the AXEN soft flask’s bite valve as much attention as its flexible body, and let the inside dry properly before storing it with the rest of your kit.

1. Empty it when you unpack your running kit

Take the container out of the vest and empty the remaining drink. Set the cap and any removable parts somewhere clean where they will not disappear among washing-up. If you used a drink mix, deal with the residue as part of this wash rather than leaving it closed up for the next run.

Before dismantling anything, check the instructions for your exact model. Find out which parts come off, which cleaning method is allowed and how the container should dry. A bite valve that is designed to pull apart is very different from one you have to force.

2. Clean the places the drink passes through

The main container is easy to remember. Give the cap, threads and bite valve the same attention, using the cleaning method specified by the maker. For a reservoir, include the tube and its connections. Otherwise, a freshly washed bag can still be connected to a hose that has not been cleaned.

A suitable brush can help reach a tube or awkward corner when the manufacturer recommends one. Match it to the opening and tube size, so you can reach the area without scraping the material or stretching a valve. Rinse all cleaned parts as instructed before laying them out to dry.

3. Give the inside space to dry

Dry on the outside is only half the job. A soft container can lie flat against itself, leaving moisture in a fold. Arrange it in the drying position the manufacturer recommends, with room for air to reach the inside. Let caps and drinking parts dry separately where the instructions allow.

Leave the clean kit somewhere airy rather than putting it straight back inside a zipped vest. Check the corners, cap recess and tube before reassembling.

Some reservoirs are designed to turn inside out. For example, the HydraPak reservoir-care guide explains this for its Elite, Force and Velocity models, and gives separate guidance for its baffled designs. Use the instructions for your own model: some soft containers cannot be turned inside out or put in a dishwasher.

4. Inspect while the parts are easy to see

With the container empty, take a quick look at the valve, seams, cap and any hose connection. Check that a seal is sitting where it should and that threads are clean. This is a convenient moment to spot a damaged component before it is packed next to a dry layer.

If a smell remains after ordinary cleaning, look for residue in the valve, tube or folds, then use the maker’s recommended deeper-cleaning method. Follow the specified product amount, contact time and rinsing instructions. Heat limits and cleaning-product compatibility vary, so a treatment suited to one reservoir may not suit another.

5. Reassemble, fill and check before the next run

Once everything is completely dry, store it as the maker recommends and keep small parts together. When you next fill it, close the cap or slider properly and check the valve and connections over the sink. A short check here is much easier than adjusting a leaking connection with your vest already on.

If something needs replacing, our replacement-flask guide covers fit, and the flask-versus-bladder comparison helps you choose a setup whose day-to-day routine suits you.