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I have tried this with mixed results.
I fashioned an elongated nozzle out of a 6mm stainless steel pipe that was long enough to reach the bottom of the cylinders. If you experiment with squeezing the end of the pipe a little, you can get a pretty sharp spray of water. I had great success with a cut-off the hose from my high pressure cleaner attached to this nozzle via a few hose clamps and a cutting ring on the pipe. I'm sure you can make a proper custom solution, but I had this stuff at hand and it sufficed.
The reason I say mixed results, was that I quickly realized that I have to fashion another bend nozzle to clean the dome of the cylinder. It was also rather cumbersome to make sure I clean every single spot of the wall and don't miss anything.
I quickly stopped using the high pressure cleaner most of the time. However, it does come in handy when an aluminium cylinder is fairly badly corroded, but not enough to warrant it throwing on the tumbler. The high pressure cleaner is great at getting the aluminium oxide out of the pits that developed and I can clean the wall and dome with the flail and the base with the wire end brush. This is orders of magnitude faster than the tumbler and I feel less messy.