Has anyone used the Sure to Grow Hail Cubes? Seems like a good alternative to hydroton or heavy bulky mediums. I was thinking about using hail cubes in net pots as a medium OR possibly filling the entire bucket with hail cubes.and wanted to run 5 gallon buckets Ebb N Flow. Are 5 gal buckets too big? Would 3.5 gallon buckets be adequate ?