I've dipped my toes in with tigs, aka Brachyplatystoma tigrinum, 3 times. This is my second tig ever that I got from George Fear of Shark Aquarium back in the Summer 2015. Came at ~3"-4". It's not easy to say what size it is today but looks about 15".
It's been easy to feed - it likes its pellets and fish, actually preferring pellets, which are nothing fancy - Zeigler Bros. catfish farm pellet (that RD. would not even feed to his fish for free, he says) at ~$30 for 44 lbs before shipping.
When it was in 240 gal, it was pretty aggressive to ~any other Brachie. In 4500 gal it appears to have been better behaved, not bothering other Brachies and no one appears to bother it. Currently there are two more Brachies in the tank - another tig at ~12" (in the opposite corner) and a vaillantii at ~15" (this guy swims all over like a boss, still has both long extensions on both caudal lobes). I had to pull out my troublesome capapretum last week as some tank mates (not sure who, never caught) were bothering it too much. I'd not be surprised if they were the three mentioned above but it'd have to be at night.
Mugshot from 2015:

It's been easy to feed - it likes its pellets and fish, actually preferring pellets, which are nothing fancy - Zeigler Bros. catfish farm pellet (that RD. would not even feed to his fish for free, he says) at ~$30 for 44 lbs before shipping.
When it was in 240 gal, it was pretty aggressive to ~any other Brachie. In 4500 gal it appears to have been better behaved, not bothering other Brachies and no one appears to bother it. Currently there are two more Brachies in the tank - another tig at ~12" (in the opposite corner) and a vaillantii at ~15" (this guy swims all over like a boss, still has both long extensions on both caudal lobes). I had to pull out my troublesome capapretum last week as some tank mates (not sure who, never caught) were bothering it too much. I'd not be surprised if they were the three mentioned above but it'd have to be at night.
Mugshot from 2015:
