Water power here can be a problem due to some pretty severe winters which in some locations can last for 6 or 7 months of the year. The Hydraulic water ram I built from plans I found in a 1932 or 1938 Popular Mechanics magazine archived in a library in California. I had to kinda reengineer that spring and cover and insulate the outflow, then bury the line all the way to my house and come up through my basement to the storage tank in the loft. After all was said and done I was glad the spring was located about 100 yards from my house. The water hammer that delivers the water makes a constant clack, clack, clack sound about 2 times per second so it would have been annoying to listen to 24/7 if it had been located closer to the house.
All these off the grid ideas in those days were do-it-yourself projects. Nobody to call for help and no phone to call with, so lotsa trial and error until you got it right.
How are the bugs in Hawaii?? Lucky you don’t have poisonous snakes there or bears either. Do you have any predators there aside from feral cats and humans?? And hot water heat from your private volcano?? Sounds like PARADISE all right!