How To Read A Fishfinder: A Complete Guide

by Matthew Price

If you are an avid fisherman or angler that spends time fishing on a boat you know the importance of a fish finder. Along with being a beneficial tool for those people trying to catch fish, they also benefit scuba divers and other individuals that love the water. It is important to note, that this tool does not benefit anyone if you do not know how to read a fishfinder correctly. Whether you have already purchased a fish finder or are looking to purchase a fish finder, it is important that you take some time to learn how to read this beneficial instrument.

Understanding How a Fish Finder Works

The first step in learning how to read a fish finder is to understand how the device works. When a fish finder is installed on a boat there is a transducer located on a bottom section of a boat. The transducer is in constant contact with the water. The transducer is the part of the fish finder that emits sonar waves into the water. The waves bounce around the water before returning to the transducer. The data the transducer gathers includes distance, speed, and the rate of the returning waves. The data is then converted into visual data. The visual data, which comes in different colored lines, arches, provides information related to the location of fish and other objects in the water.

Features of a Fish Finder

When you are learning how to use a fishfinder you have to understand the different features of the device. Learning how to read a depth finder is important. Reading the visual and numerical data on the depth finder you will be able to see how deep the water is beneath your boat. Knowing the depth of the water also helps determine what types of fish are in the area. Typically, the depth is located on the top left of the fish finder’s screen. In most cases the depth is given in meters as opposed to feet.

When learning how to read a fish finder it is also important to know where to find the water temperature. On many fish finders you will find the temperature of the water right below the depth reading. The temperature of the water is beneficial as it can determine which fish are present. As most avid fisherman knows, certain fish prefer and even thrive in different water temperatures.

When learning how to read a fishfinder it is very important to understand how to read the SONAR echoes. Whereas all fish finders display SONAR echoes on their screens, they differ from one device to the next. In some cases the sonar echoes are displayed in black and white. In other fish finder devices the sonar images are in colors. When the fish finder has a color display the colors are directly related to how hard and how dense the object the sonar hits (check our main guide to make an idea about top fishfinders). Typically the seabed is the darkest color shown on the screen. When the color is lighter it is an indicator that the material is soft. As an example a lake with a soft bed of clay will display in a lighter color than a less porous and firmer material.

The seabed is not the only thing the sonar picks up. Groups of fish, or schools, can show up as groups of color. Single fish appear to be dots or almost smudges, depending on the size and shape of the fish. Colors and lines at the top of the screen can display objects at the surface of the water and water movement around the transducer. It is also possible to see where coral reefs and rocks are located. Once you have an understanding of how your fish finder’s display works you can even zoom in to better understand and identify what is sitting in the water below.

In order to get the most of your fish finder you have to understand how to use a fish finder. The above guide breaks down different features of all devices available, which can help with usage. The guide above explains not only how to read each of the different features, ranging from the depth finder to water temperature and SONAR echoes. The guide also explains how each of these features can benefit the user, whether they are looking for fish or other items sitting on the seabed. Although learning how to use a fish finder may be tricky at first, once you understand each of the different features fishing or scuba diving will be a more exciting and hopefully productive time. If you’re a beginner user it can be good to get a cheap fish finder to upgrade later with a better model.