Eel Aquaculture

[e...@stowers-institute.org]

I recently purchased a pair of Eels from a local Asian market here in
Kansas City, MO. They are very tough, as the guy who put them in my
bucket just added city treated tap water to them, and they were in a
tray that was highly crowded for who knows how many days, but are more
than a week out in my aquarium and look great. They are Anguilla
japonica, but they lack the pectoral fins, and when I search for images
of Anguilla japonica the majority have pectoral fins. Anyone know why
this might be?

Fishbase lists their Importance: fisheries: highly commercial;
aquaculture: commercial.

Anyone know of any protocols for culturing?
I'd also like to know how to sex them.