The vast majority of worms will prove to be harmless or at the
predator of other small worms and pose no threat to the larger
life forms that we place in our tanks. Of course there are
exceptions. While some worms can grow large and seem threatening
they are in fact a vital part of the clean up crew, taking care
of unseen livestock deaths and left over food. this clean up
service that they provide that has led to some species being
labeled as fish killers as they are usually blamed for such fish
losses when they are seen on the corpse of the fish doing their
job of cleaning house. In the hopes of saving you some confusion
as has happened to me quite a few times, I am showing a few
examples of the rear sections of various worm species as they
can be quite easily confused for the worm's head. A great many
of the worms can be very lengthy and it is very common to break
the worms while trying to remove them from rocks. Of course a
good many times, I end up with the wrong half. To further
mislead you, the worm, ev