LifeStraw Home | Filter Housing doesn't emptyUpdated 11 minutes ago

If you notice the filter starts flowing after you pour water in, but then slows or stops once the water level reaches a certain point and a small amount remains in the upper chamber, that is normal.

This happens because the water pressure inside and outside the filter equalizes. When the flow pauses, add a bit more water to the housing. The added water increases pressure and filtration will resume.