All my fishes were bought young and have grown together, they have plenty of room to spread and enjoy themselves without bumping in eachothers.
Also my aro dislike fish taste, when I try sometimes he just ignore it and only eats frozen shrimps, live lizards, and various insects I catch in my garden.
I just hope it'll stay that way once the aro is fully grown.
I'll try to shoot another video while I feed them this weekend
a small update with a video (720p available) a friend shot from outside during a bbq at night. You can see my aro grabbing a bite at 1:05
[YT]b6f_SZDF8eI[/YT]
My aro is doing great, he's now almost 18" (was 9" in december 2011 when I got him), the giant gourami is growing at the same pace and is about the same size, the knife fish is the longest with 19" (was 6" in november 2011).
A 12" pleco joined the pondarium, a friend of a friend had it in her pond and it was fighting with her goldfishes ... he's doing fine and is often sticking next to the knife fish.