Hey guys, my first time posting in this forum.. My question to all of you is.. I al looking at creating a boulder (round) with a 1 inch drill all the way through... I then want to have it sit on a bed of river jack so when the water flows off of the rock it is collected here. I want it to be 'waterless'? Meaning no standing water.. Im sure there is a technical term for this. Anyway can anyone shed some light on how to create the water collection under the river jack? Thanks.