An elevated air hose can't act as a water trap because the moving air will push the moisture up the line. In my work, we use compressors on the ground and run hoses up 4-5 stories, and the moisture still spits out of the hoses and tools if the compressor hasn't been drained properly. I use an 8 gallon for airbrushing, and I have yet to put on a water trap. It's only a matter of time before moisture creeps into my line, so I better get on the ball. IT IS NEXT TO IMPOSSIBLE TO CLEAR MOISTURE FROM A HOSE. You may get most of it, but once it's combined with dust and traces of oil (on oil-lubed compressors), it will continue to give you problems. Just buy another hose.