Dear Fran!
Since water is another element you like to live in, I have a mayby totally silly question that nobody I asked before could answer.
What happens acoustically if you pack water in a foil (like those used for artificial ponds in gardens). I think water has no special resonance but relatively high weight. It will be moved because of its flexibility and therefore absorb/transform some energy. You can shape the foil in any way and if you drain off the water transportation is easy.
Do you see any sense in this?
Please excuse if this is crazy.
Peter Zeman