Is nematode a parasite or a fish food for small fish?

[gu2high]

I am wondering whether nematode a parasite to small fish or a living food for them. The fish I am talking about are guppy, platy, barb, tetra, cory cat, etc.

 

[Devilishturtles]

Nematodes are harmless, usually indicate excess nutrients in your water. Fish should find them a tasty snack.

 

[toddnbecka]

I occaisonally see the betta snatch one up, and he's been hanging around for over a year.