At the current time they appear not to have been bred in captivity. No obvious differences are visible between male and female Black African Knife fish (Xenomystus nigri).
black ghost knife fish gets nutrients and energy from the food it eat
No.
No.
they can be 49cm.
fish about 5in or 4in lowest
The maximum length of the black ghost knifefish is 40 centimetres
Yes it can
Black Ghost Knife Fish are semi-agressive. They should be fine though. The angelfish should be fine.
Depends what store!
It uses an electrical field produced in the fish's body.
The fish must be small enough to be eaten by the knife. There are also small shrimp (ghost shrimp) which some small knifes will find easier to catch than the faster guppies. As the Knife grows so will it's prey.
The same place every other fish gets its energy. From the food it eats.