Black moors are a variety of goldfish which are egg layers so they can't get pregnant.
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.
Your fish can not be pregnant so don't panic. They are egg layers so their eggs are fertilised and the young hatch out in the water not in the fish. Black Ghost Knife Fish (Apteronotus albifrons) grow to over 20 inches long and need a very large aquarium (at least 6ftx2ftx2ft) and are extremely hard to breed so the chances of you manageing it with your lack of knowledge (of the species) are very unlikely.
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.