The most common way of removing the hose from a barbed fitting is to take a knife and cut down the hose. While that is efficient, it can do more harm than good. Using a knife or razor blade to remove the hose can damage the barb on the fitting and lead to a leak.
Instead of using a knife, remove the hose with a soldering iron. Just add a plastic cutting tip to it and bend it 90 degrees so it acts like a cutting blade. Then, after letting it heat up, slowly use it to cut down the hose.