Me and my buddy just made one last night out of 4" sewer tubes. To get right to the question. My buddy took an end cap, cut in in half to create a little bit of a dam on the end where in drains back into the resivor. I'm just worried, since when the pump (560 gph) is running, the level of water in the pipes is about halfway. Would'nt that be taking a chance of drowning the roots? Should the water be at a lower level and just basically run a constant flow at the bottom of the tube instead of being half filled with water all the time? Hopefully u can get a idea of what I'm saying without a pic.