Black ghost knife and little fishes?

Question

Can I have my black ghost knife fish live with swordtails and guppies?

Answer 1

As an adult, the Ghost Knife will have no trouble snatching up Guppies of any size.  Swordtails, however, will get large enough to avoid being seen as food for the Knife.  Larger Tetra species (Black Skirts, Red Eyes, Congos, Diamonds, Rummynoses, and Buenos Aires) and Tiger Barbs would also be good choices as long as you get a good number of them.

Answer 2

you won't have any problems at all! enjoy!