Originally Posted by huma-huma
I mean technically there would be a way to measure the displaced water volume, as long as you had a baseline for how much water 1 lb displaces. You should be able to get close
Wouldn't that still require pulling all the rock out? Or draining the tank & measuring how much water was in there? Either way, you'd have to remove all of the water OR all of the rock to see/measure the diff. Might as well weigh it! Plus IDK if all my rock came from the same source or what density it is or would even be able to guess the density due to not knowing what type of rock it is. But yeah, if I had no scale. Water displacement could be a good measure!