How To Read A Fish Finder? Tips To Catch More Fishes


How To Read A Fish Finder? It is a question that fishers have been asking for centuries. And even though technology has changed a lot since then, the answer is still not simple.

Because there are so many different features and functions on fish finders, it can be very difficult to figure out what each means and how we use the fish readers to our advantage.

This blog post will break it all down for you and show you how to read a fish finder. So whether you’re just starting or using one for years or looking to improve your skills, read this article.

Fish Finder Basics

To understand how to read a fish finder, let’s first go over the basics. Fishfinders use sonar to detect and locate fish in the water. Sound waves are sent out and bounce off objects in the water, and their return time is calculated.

A fish finder graph is then generated based on the information collected by the sound waves. Besides showing you where the fish are, this graph shows you the depth they are at and what kind of structure surrounds them. Now that we’ve covered the basics, let’s move on to the fun part – how to read a fish finder!

How To Read A Fishfinder Screen?

How To Read A Fishfinder Screen

The first thing you need to know about how to read a fish finder is that there are two main types of screens – traditional and split-screen.

A traditional fish finder screen will display all of the information in one place, while a split-screen fish finder will have two separate screens displaying different display actions.

No matter which type of fish finder screen you’re using, it displays the information in a graph. The x-axis (horizontal line) represents time, while the y-axis (vertical line) represents depth.

The transducer emits sonar waves, usually mounted on the boat’s hull. Waves bounce off fish and objects in the water.

Once the waves have returned to the transducer, the time required for them to do so is measured and used to calculate the object’s depth. An array of dots represents this information on the graph.

The distance between their dots measures objects. The proximity of the dots indicates the close relationships between the fish. Spread out dots refer to spread out fish.

Identification Of Fishes On A Fish Finder Screen

After you’ve learned what a fish finder is used for, let’s discuss how to identify different fish species on the screen.

Identifying a fish is largely based on its shape. You can distinguish different types of fish by the shape of their bodies.

By Icons

By Icons

Different icons on some fish finders will represent different fish. While these icons are useful, they are not always accurate.

You can use an icon you think represents a fish as a guide, but do not rely on it completely to help you identify the fish.

By Arches

By Arches

On a fish finder, you can also identify fish by the shape of the arch they appear on the screen.

Every type of fish forms a different arch depending on its body shape. Short and round fish create a thick arch, while long and skinny fish create a thin arch.

Determining The Fish Size

You can also use fish finders to determine the fish’s size and shape. The arch will be larger if the fish is larger. You are likely to find a big fish if you see an arch on the screen.

Fish Arch Width/Length

Its arch’s width or length can also determine a fish’s size. A fish’s body length determines the width of the arch, while its depth determines its length.

So, if there’s a long and skinny arch on the screen, it’s likely that you’ve found a long and skinny fish!

Half/Full Fish Arches

A fish finder is also helpful in determining the fish is swimming towards or farther from the transducer.

  1. A Fish swimming toward the transducer, the arch is “closed” or “half.”
  2. A Fish swimming farther from the transducer, the arch is “open” or “full.”

Locating Batfishes On A Fish Finder Screen

Now that you’ve mastered reading a fish finder let’s talk about locating batfish on a screen.

Batfishes are small, round fish that create a thin, straight arch on a screen. Batfish usually live in large numbers. You can expect to see many more nearby if you are lucky enough to see one on the screen.

Look for a thin, straight arch on the screen to find batfishes. The arch will be longer than wide, and it will be straight, not curved.

Once you’ve found a batfish on the screen, keep an eye out for other batfishes nearby. They’re usually found in schools, so there are likely many more nearby if you see one batfish.

Locating Trophy Fishes On A Fish Finder Screen

Trophy fish produce an arch of thick, curved lines on the screen. There will likely be a few others nearby if you live in groups or by yourself.

So, if you spot a trophy fish, you can find it on a screen with a thick, curved arch. There will be a curved arch rather than a straight one, and it will be wider than it is long.

Keep an eye out for additional trophies after discovering a trophy fish on the screen. When you see one trophy fish, you can be sure that several more are nearby.

Identification Of Underwater Structures On A Fish Finder Screen

Your fish finder can also help you find underwater structures, such as reefs, sunken ships, etc. Fish can use these structures to hide as well as to avoid.

You can use a fish finder to detect underwater bodies by searching for sudden depth changes. You will likely find a reef nearby if there is a deep water section at the edge of a shallow section.

In-depth changes to the screen will also indicate sunken ships. These organisms are generally larger than coral reefs, so they are easier to spot.

Fishfinders are also beneficial for identifying areas to avoid, such as rocky shoals. On a screen, these areas look shallow and flat.


Weeds and other vegetation will also appear as shallow, flat sections on the screen. However, they’re usually not as large or easy to spot as shoals.


Like caves and trenches, they will appear as dark areas on the screen. Lighter areas usually surround them, so they’ll be easy to spot.


Thermoclines are layers of water with different temperatures. They can provide hiding places for fish and areas to avoid.

Other Objects

You may also see other objects on the screen, like logs, rocks, and more. These objects will usually be easy to spot, appearing as dark areas on the screen.

Remember that not all objects on the screen will be fish or underwater structures. Sometimes, you may see objects like logs or rocks. These objects will usually be easy to spot, appearing as dark areas on the screen.

Identification Of Different Types Of Bottoms

If you’re fishing in an area with a lot of vegetation, you may see different types of bottoms on the screen. These bottoms provide hiding places and areas to avoid fish.

Mud bottom, rocky bottom, and weed beds are some of the main types of bottoms that you will encounter while fishing.

Here is how you can identify them on your fish finder and what type of fish you can expect to find in each:

Mud Bottom 

A mud bottom will appear as a dark blob on your screen. It is usually soft and mushy to the touch. Fish that typically inhabit mud bottoms include catfish, carp, and suckers.

Rocky Bottom

A jagged line pattern will appear on your screen if you place a fish over a rocky bottom. The rocks are usually hard and sharp to the touch. Trout, bass, and panfish are popular inhabitants of rocky bottoms.

Weed Beds

A weed bed will appear on your screen as a tangle of tangled lines. The weeds are usually soft and flexible to the touch. Sunfish, crappie, and perch are among the fish that frequent weed beds.

Sand Bottom 

The bottom of the aquarium is usually a smooth, featureless area on your screen. The sand is typically soft and gritty to the touch. Flounder, sole, and whiting are three species that frequent sand bottoms.

Gravel Bottom

A gravel bottom will appear as a string of tiny, circular dots on your screen. The gravel is generally abrasive and piercing to the touch. Trout, salmon, and char are among the fish that frequent gravel bottoms.

Frequently Asked Questions [FAQs]

Frequently Asked Questions

1) How To Read Down Imaging On A Fish Finder?

You can look under your boat with down imaging. Watch for sharp changes in water depth on your fish finder when reading down imaging. You can find a coral reef near a deep water section and a shallow section.

In-depth changes to the screen will also indicate sunken ships. These organisms are generally larger than coral reefs, so they are easier to spot.

2) How To Read Side Imaging On A Fish Finder?

Side Imaging is a popular feature on many newer fish finders. It allows fishers to see a 360-degree view of the underwater environment around their boat.

To read Side Imaging on a fish finder, start by looking at the display. There should be a series of lines representing the different depths of water around your boat. The outermost line will represent the shallowest depth, while the innermost line will represent the deepest.

Objects close to your boat will appear on the left side of the display, while objects that are further away will appear on the right side.

3) What Is The Most Appropriate Frequency For A Fish Finder?

There is no definitive answer to this question as it depends on several factors, such as the type of fish you are targeting, the water conditions, and the level of experience of the fisherman. However, as a general guide, most fish finders operate at a frequency of 200kHz, which is suitable for most types of fishing.

4) What Do Fish Look Like On A Fish Finder?

Fish will appear as small, dark dots on your fishfinder screen. The number and size of the fish will depend on the species and the size of the school. If you see many small dots on the screen, you have likely found a school of baitfish.

5) How Does A Fish Finder Work?

A fish finder uses sound waves to detect the presence of fish. It then uses a transducer to convert the sound waves into electrical signals. These signals are then displayed on the fish finder’s screen, which allows you to see where the fish are.


Reading a fish finder is fun, but not everybody can use this tool. You have to learn some tips and tricks and practice a lot before reading a fish finder accurately.

Here, we have discussed the most precise and accurate method of reading a fish finder. So, go through this article, and you will become a professional in reading a fish finder.

Thus, that’s all about how to read a fish finder. Please let us know your thoughts in the comments section below if you like this article.

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