I just updated our larger hydroponics tower structure (it holds 10 towers) with the same water return setup that I did the other one last week. This looks much better and holds the towers perfectly (I hate spinning towers). Unlike my other tower structure, where the water reservoir is below the towers, this one has the reservoir at the left side. Because of this, I only capped the other side of the PVC post. so that the water drains into the reservoir to the left.