My setup is over carpet scary yes but at least I will not break my test kit. Setup my lava rock and 2 inches of river rock for the top in one grow bed. Found that my bulk head leaks for my stand pipe. I tested both grow beds for leaks before adding the rock and had no leaks. My guess is the weight from the rocks stressed the silicon joint. I have 3/4 inch pipe for my drains any suggestions? I found conduit fittings that screw on both sides that might work with washers. What is everyone else using for this?