g33tar, Brohawk gets credit for the drop checker design, I just took his idea and ran with it.
gogreen, I've spent about $15 on all the tube that I've played with. I'd say that half of that was wasted just figuring out that it could be done. Now there is very little waste. In fact I bought a used set of glass lily pipes for $30 just so I had a real live comparison. For that amount of acrylic tube you could make 15 sets of pipes.
Robotguy, nice job, but remember I said patients. A thought if you want to cut the slots on the inflow before bending you can still fill it with salt. Just tape over the slots then fill it up. I've thought of the inline diffuser also but have a some that I've bought before I decided to get creative. Let us know how it works once you get it all set up.