I used GE 100% silicone this time.
Don't be scared to try this. The only expensive part was the drilled bottom. The other pieces cost less that $4 each. If you don't mind visible hoses or an HOB filter, you could make one yourself for around $25 (glass and silicone). If it doesn't work the first time, cut it apart and try again (like I had to do). Worst case, you give up and you're out less than the cost of a trip for 2 to the movies.
The glass store accidentally made me 2 bottoms (12" x 12" x 1/4" w/2 holes drilled). If anyone is interested in risking shipping it (I could make a little wooden crate for it out of scrape) or your local in San Diego and want to pick it up. I'd be willing to make a good deal for it.