lose the arowana"120Gallon
1x silver arow
1x pleco (common)
1x catfish (dont know what type yet)
1x Pike (dont know what kind yet either)
How about keep the aro, get some Geophagus or nice Discus as your cichlids and keep the rest of it Amazon...
Check out the introduction pic on Frank from the Netherlands site, you'll get the idea, although I think his tank may be a little bigger...
...and play the "Tank today" vid on the "My Tank" page as well, it's great.
P.S. 2 Jags is our deputy Prime Minister over here...don't know if he'll fit in 120 gallon...