Man, I always loved your DWC tutorials, I modeled mine after yours posted on Overgrow. This setup looks a LOT cleaner, and easier to maintain... I love the 3/4" ebb&flow fittings for holes, that is a killer idea... no leaks!!!! No silicone!!
What was the main reason you took down your old system? This looks to be your 3rd or 4th DWC rebuild.. what gives? Although, I must admit, with each rebuild things look cleaner and easier, could be enough reason right there.
One of the best tutorials I have ever read on any website; clear and concise.