Here's a look at one of my big boys, Anguilla bengalensis. He likes using the two corner overflows as caves. It used to be pretty irritating not having him in the main tank, but it seems content in the overflow so I'm not really bothered by it anymore. If anyone wants to stick there hand in there to get him out, be my guest. Otherwise he only comes out to swim across the tank into the other overflow. 
Enjoy!
[YT]rjlDhOusqoE[/YT]

Enjoy!
[YT]rjlDhOusqoE[/YT]