I feel silly for only just realising, but the whole cap from the Salomon soft flasks comes apart allowing you to give them a good clean : r/ultrarunning
Salomon Outlife 550ml Soft Flask Clear | Trekkinn
HOW TO CLEAN WATER BOTTLES, FLASKS AND BLADDERS – Salomon Sports
Run Hacks: How to keep hydration bladders and soft flasks mould free - YouTube
How to Clean a Soft Flask - Home Explained
Advice on how to properly clean the tip of salomon soft flasks. Energy drink mold 🙃 : r/trailrunning
How to clean water bottles, flasks and bladders – Salomon Australia