In my opinion Severums are quite peaceful and calming to watch. They just kind of float around, long trailers streaming behind, and aren't terribly aggressive at any time. I have 14, and I love watching them.

I totally agree. The most relaxing fish I've ever had, were long finned fancy goldfish.I think this situation calls for fancy goldfish, maybe fantails, lionheads, or orandas. Viewer relaxation is exactly what they were bred for, and you could keep a nice group of them in a big tank, especially that 125.
:iagree::headbang2:Arowanas. There's just something...majestic about them.
http://www.youtube.com/watch?v=6BDeDI9bC2k
http://www.youtube.com/watch?v=wkUMd75BBiw&feature=related