God I wish that video had never been posted to the internet.
That GATF is around two feet long. That means the fish is no less than four or five years old; likely considerably older. The arowana in the video is less than a year old, likely only a couple of months. If you were to acquire a six inch GATF and a six inch aro and put them in a tank together, in less than a year, the GATF would be in VERY real danger of filling the belly of the arowana. The arowana is a MUCH greater threat to the GATF than the GATF is to the arowana.
If you don't believe me, look at what an eighteen inch black arowana did to a foot long GATF:
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