How To Read A Fish Finder Screen: Beginner’s Guide to Success

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Are you a beginner of fishing? If yes, one question always in your head is, “how can I read a fish finder screen?” If you ever asked yourself such a question, then you are at the right place! This article will show you how to read a fish finder screen.

Understanding And Interpreting The Display

Apart from the best fish finder enabling you to see what is under the boat, you will also have a clear view of the fish’s response to the bait, and you will be able to spot where they congregate easily.

Many fish finders create images in the water using imaging sonar technology to shoot beams down, getting a tiny coverage of the bottom part. Despite not getting the preferable results from the coverage, some tricks can be used to ensure an accurate reading.

Fish Arches vs. Fish Dots

Fish arches form whenever the transducer moves above the fish or whenever the fish is moving past the sonar beam. The fish will first have to enter the beam on one side and get out from on the opposite side.

Fish dots are the baitfish that are displayed on the fish finder. The Baitfish group can be seen in balls and is suspended on top of the water. They can also be in yellow colors or green.

Reading Fish-ID to identify fish

Learning fish finder basics is one of the first things you must do. You will find it much easier to attract fish when using fish finders with fish-ID technology.

Fish Icons

The type of sonar signal most fish finders uses will help locate the small fish icons. You will see them in varying lengths and sizes. The good thing is that you can always view the different rocks, plants, and fish school icons.

All you will have to do is read the displayed icon on the screen and understand the displayed icon’s depth.

This fish finder type displays rocks, vegetation, and schools of fish. All you have to do is read the fish finder screen and paired icon. You will know how big it is after doing that. However, there are no perfect fish finders, and there are always downsides.

Fish Arches – 5 easy steps

You will always receive lines and arches from the transducer whenever you have the arch fish finder. With this type, you can be sure of saving lots of your time since you will easily and quickly understand how they work.

Fish arches will ensure you quickly understand how the fish finders work.

Whenever the fish finders indicate larger arches, it will mean a big fish has been detected, while the smaller arch will represent smaller fish.

Although it can be cumbersome to identify plants and rocks among the arches, you will understand how fish finders work to help identify structures and classy fish depending on their size and location.

Judging Fish Size

As you already know, a larger arch represents the bigger fish. However, sometimes it couldn’t be true in some scenarios. Not all devices shows info correctly because of old programming version .

Fish Arch Width

When the fish finder technology does not indicate the actual fish length, will it display the arch width? Yes, most likely, you will get the actual fish size when you look at the fish arch width.

Here is a tip:

Learn about the arch thickness rather than the size. When the fish finder gives a full arc return, it is highly possible it is a big fish. When you get a fish school of similar size, spotting the biggest fish with the thickest size will be much easier.

Half Or Full Fish Arches

Fish finder arches can be half or full arches. The fish finder screen will reveal a full arch when the fish covers the whole sonar cone. However, it will display a half arch when the fish swims and covers part of the sonar cone swimming.

It is important to note that half arch is only sometimes a small fish. There are possibilities it can also be a bigger fish.

The arch size will not show if it is a smaller or larger fish. We recommend that as a fisherman, you always keep an eye on the arch thickness since this is the most reliable method to help reveal if a fish is small or big.

Finding Baitfish on Your Fish Finder

Unlike the traditional sonar, the bait fish will always display on the modern fish finders as lines, dashes, or dots. The Baitfish group will be seen in balls and are always floating in the water. They will also be visible in yellow colors, and vegetation’s green color.

Spotting A Trophy Fish On Your Fish Finder Display

Going through the previous tip, we illustrated the best method to locate a trophy fish. Looking at the fish arch width or thickness is the best indication to reveal whether you have seen a bigger fish.

Regardless of whether the arch is half or full, always keep an eye on the arch thickness as the main indication.

Identification of Underwater Structure Types

Anglers can read the depth and underwater contour structures with ease. This will help them easily locate fish, especially when they can interpret the screen readings and you are conversant with chirp sonar. You will have a wide view thanks to the depth finder feature.

The transducer’s depth finder will enable you to know the depth of water below your boat. It will also reveal the fish type to expect in that lake or river.

In most cases, the depth finder feature is always available in imaging fish finders and can be seen in the screen’s left corner. It uses the meters and not the feet since it is a scale measurement.

Apart from this, the depth finder will also perform a fantastic job of revealing the water temperature, which will help you understand the fish type you will be catching.

Ensure you are constantly scrolling or trolling the new fish finder at a slow speed to have an accurate and clear view of the contoured bottom. It will increase your chances of successfully identifying the drop-off.

When you identify the drop-off, switch from a wide beam to a narrow beam scanning to scan the entire area again.

Vegetation And Weeds

You can settle on areas with plants and vegetation as your cast areas.

The fish finder will indicate a spotter and vertical lines when you approach vegetation or weeds.


When you are interested in spotting depressions whenever you are carp or ice fishing, always watch out for the small V-shape dips at the bottom contour when reeling or strolling. 


Spotting points is much easier as they are more gradual when compared to drop-off. To ensure you get the correct reading of the incline steepness, you have to stroll or reel at a steady speed. You also have to make sure you use a narrow sonar beam to scan as it will give you clear shelves and humps reading that wider beams may fail to pick. 

Judging bottom Types

The fishing location can vary between soft mud, hard rock, and grainy sand. The fishing methods we use need to change depending on these factors. This information will help make you a better angler. 

Hardness / Thickness

You must keep a few things in mind on how you read a 2D sonar fish finder to help you determine the hardness level and type of bottom below.

You will know if the river or late bottom surface is hard and rigid when the fish finder returns a thick and bold line and produces a loud echo. The bottom is soft if it returns a thin and light line.

Color palette darkness and return to the transducer’s echo line will determine the bottom’s hardness.

When you have a lightly colored line, it will mean the bottom is soft. However, a loud echo and a solid coloured line will mean a rigid base full of rocks.

Live Sonar: Watch how your lure works

You will start by choosing the type of lure to use. You can experiment with a wide variety of lures.

Using a lure to fish imitates the movements of fish’s prey in the waters.

Get the correct lure technique to use. ‘Walking the dog’ is among the most influential and common lure techniques.

Apply the right fishing tips, such as not jerking the line too much.

Watch how lures work :


Keep in mind that knowing how to read fish finder screen and being able to interpret the readings are two different things. We hope this article has helped you understand how to use a fish finder, read a fish finder screen, and identify the different underwater structures. You can now go out there and get some fish. All the best!