Me either.
Exactly. Mbu are not exactly what I would consider a high energy, glass banging fish.
The tank in the link below is owned by a local person, a close friend of mine. (550 gallons, with a 130 gallon sump for filtration)
http://www.monsterfishkeepers.com/forums/showthread.php?t=307959
The largest arowana in that comm tank was 30" (fish on the far right in the second pic) when that photo was taken, and it had no issues moving around
comfortably in that tank. That tank (along with all of his other tanks, including another 550 gallon tank) is on an auto water change system, with that tank receiving 100+ gallons of fresh water on a daily basis. Nitrates never exceeded 10 ppm, and were typically in the 5 ppm range. I find it absurd to think that my friend couldn't house a single mbu in that system, based on that tanks size, filtration, or its water quality.
I suspect that if RTR had started out with such a system we would have never read about his 1,000 gallon min tank opinion.