two Males or two females? they are fighting over territory tring to find out who is the superior one. if 1 male and 1 female i think you know
If you mean ragged fins then this is probably because another fish in your tank is attacking it. Any type of barbs are notorious for attacking fish with long fins and angel fish will also have a good go. It is difficult to say who is the culprit for definite without knowing what you have in there, but this is generally the reason. Hope this helps.
male fish are territorial he is claiming his territory
Sea lampreys do not pose a threat to humans by attacking them. They are parasitic fish that primarily feed on the blood of other fish species.
fighting fish are known for attacking preditors when being invaded or having their young attacked
a siege
Claim to all the fish in the Pacific
yes they can.
My goldfish Fan tail is attacking my small gold fish, they have been together for over a month now but has only recently started to nibble at the smaller goldfish, how can i stop this
you cant. you have to remove the fish before it does further damage to other fish.
Another mane for 'Devil Fish' is 'Poo Fish'.
If possible, yes, you should try your best to stop your friend from attacking another person. However, if your friend is attacked first then they will have to defend themselves.
Another name for a flying fish is a Ray-Finned fish.