I KNOW THE GUY WHO GAVE THE GIANT PACU TO THE NATIONAL AQUARIUM!!! I met him in this fish store called "House Of Tropics" Apparently, it got too big for his 500 gallon and he couldnt find anyone with a big enough tank for it so he gave it to them...
The RTC was around 3.5'. Not moving at all he looked to have spine issues. The Niger cats were the biggest I've ever seen. The pacu was also the biggest pacu I've ever seen. Had to be 6" wide and looked to be the same size as the RTC.
No cichlids beyond the discus and Africans. The discus weren't even the showpiece they were in a planted display. No cichla, but I posted a pic of the striped bass enclosure.