The machine will not differentiate between fish and other objects in the water,.....the fish icons are just a gimmick.
You may have a sensitivity button on your machine that will allow you to decrease sensitivity so you don't pick up every piece of floating debris under the boat.
you can probably shut off the fish icons too which will help.
when the sonar picks up fish they look like upside down boomerangs on the screen......bait will look like a cloud.
spend some time futzin with it and you should learn to use it well enough.
You may have a sensitivity button on your machine that will allow you to decrease sensitivity so you don't pick up every piece of floating debris under the boat.
you can probably shut off the fish icons too which will help.
when the sonar picks up fish they look like upside down boomerangs on the screen......bait will look like a cloud.
spend some time futzin with it and you should learn to use it well enough.