An ostomy bag with a filter construction is provided. The filter construction includes a deodorising element and an extension element. The extension element may function to provide buoyancy means so that a gas-inlet portion at the extension element is kept on top of the output or pushed away by the output. The extension element may also be attached to the ostomy bag at a distance from the deodorising element so as to provide a controlled flow path for the gas-flow.
