Some fish species can make audible sounds like clicks or croaks but most fish communicate with body language. Certain species will flare out their gill plates the same way a cat would raise the hair on their back. They try to make themselves look bigger and more intimidating to scare away another fish from their territory or when they are defending their young. Some fish will turn their body sideways to appear larger if they are challenged by another fish, while another tactic is to grab another fish by the lips. Sometimes they will wrestle this way and even may tear off the lip of another fish during a fight. Some fish will "lip lock" to test each other if they may be a breeding pair. If they both "tough out" the fight then they know they are both strong enough to raise young together. Another way fish communicate is to "color up". Their normal coloring may appear dull or pale, but when they fight or breed, often the colors get really strong and vibrant. Cichlids are one type of fish that show a lot of display. You can visit the cichlid tanks at your local fish store and often see a lot of fish interaction if you know what to look for.
Different fish communicate in different ways. Some can make clicking or croaking sounds by rubbing their fins together. Body language is another way fish communicate. Fin flaring or sudden color changes can indicate breeding behavior or even illness.
Different types of fish use different methods of communication. Carp and their close relatives use pheromones – hormone chemicals that act outside the body. All the cells of the fish produce pheromones and, as the fish matures, it learns to detect these signals and respond to them.
For example, when a carp is injured, it releases large amounts of pheromones into the water around it, as a result of trauma and stress. The chemical signals are detected by other fish of the same species and they interpret this as a signal of extreme danger and they swim away from the signal as fast as they can.
Other fish produce sounds but this may be more for display than communication. The satinfin shiner, a North American Minnow produces a high pitched purr by releasing bubbles from its swim bladder. Males also produce a sharp knocking sound when they fight. Females partnered to the males can recognise the sounds made by their own mates.
More with body language rather than voice. Many fish will follow along their tank while you walk along the floor. You can replicate fish behavior to get a response from them, but it does not mean they actually "understand" you. Many cichlid species show breeding or fighting behavior by "facing" their opponent and shaking their head from side to side, and they smack their mouth open and shut several times. If you were to look at them through the glass and perform these behaviors, you may get a reaction from your fish. Usually they will be intimidated and swim away, or they may stand their ground and face off with you. Be careful doing this, because you may raise aggression in your tank and it may cause one fish to attack another since they can't get to you through the glass.
Well fish move and when they move up they are saying that they want to mate and that non of the other fish deserve them. Also when I fish has missing scales and their was more than one fish in the tank it means they were just raped and they are scared. If a fish falls out of the tank and is dead on the floor they were not pushed they jumped they were sick of looking at your ugly face all day long. Oh and one more thing you need to get a life If you are looking up how fish talk to each other!!!!! But don't feel left out I need a life too I mean I wrote this long possibly retarded speach all about something I don't know anything about. God I hate my life! I think I'm going to be just like your fish and kill myself.
