When I was talking to John Roppel last weekend, he told me that bulkheads are readily available and cheaper than aquarium supply places if you simply go to a marina! Makes sense, boaters have a lot of reasons to move water out of one spot and into another. I sure intend to try that approach, as I have a lot of trouble figuring out what the diagrams and shorthand on the webpages mean, I want to hold the thing and look at it.