I like your placement of the diffuser the longer the co2 is in contact with water the better your system will work.
I love all the plant choices. I'm interested to see how the foreground plant will turn out!
The moss on the wood is a nice touch! ~LiquiD~
Nice setup. Cant wait to see it once its grown in. I would hide as much of the "inner workings" as possible. Other than that and a little growth, awesome man.