All Cichlids and Anabantids are territorial. Fish that protect their young and the area they have chosen to rear them in are called territorial. Many other species of fish are territorial too but there are too many to list them all here.
Some fish are very territorial.
male fish are territorial he is claiming his territory
Probably because they are just very territorial.
you can put a put a clown fish or a angel fish but you have to have a lage a place to hold the fish because angel fish a a little territorial
Yes they can, but with care, they are territorial. I have two of them and they have bitten the fins of other fish.
it could be for territorial reasons.
Yes. Some species are territorial and will do as you said.
Fighting fish are territorial and can be very aggressive, they will kill other fish if you put them in the same tank.
No most fish are friendly but alot of fish like sharks are very territorial just leave them alone and you probably won't get attacked
They are territorial by nature and they compete to court sometimes
I suppose it is possible. Beta are very territorial fish.
Fish can sometimes become very territorial, try moving the item to a different location in the tank.