TrollingMotorPro may earn commission from affiliate links in this article. Learn more.

If you have a trolling motor already, you know how much a piece of technology can transform your fishing.

There is one more piece of equipment that can dramatically improve your fishing experience – a fish finder.

In this article, we’ll talk about the main reasons anglers buy fish finders and go through the main features a good fish finder should have, and tell you which fish finder models and combos we recommend.

Let’s get started!

How Does a Fish Finder Work?

Every fish finder has two elements: a display unit and a transducer.

The transducer creates sound waves, which are then reflected by underwater objects.

These reflected waves are then received by the transducer and used by the display unit to calculate the object’s distance and how hard it is.

5 Reasons To Get a Fish Finder

1. You Can See What Lies Under

A good fish finder will help you visualize the bottom, its physical features, the structures, and the feeding fish.

Understanding what is going on under your boat allows you to adjust your behavior accordingly – how fast you should be moving or at what depth you should target your fish.

2. You Can See Where the Bait Is

Most anglers know that some fish like bass, catfish, and many others, follow the bait they prey on. Bait can often be hard to see on the surface.

With a fish finder’s help, you can see schools of bait that your target fish is looking for. By following the bait, you increase the chance of catching your target fish.

3. You Can Mark a Fishing Spot to Return to It Later

Most of today’s fish finders are equipped with GPS and let you mark spots and tracks you can later go back to.

4. You Can See Underwater Structure

A fish finder can show you where large underwater structures are, some of the best places to catch fish.

5. You Can See Temperature Changes

Knowing how the temperature changes with the seasons and from place to place, is essential to understanding where the fish might be.

Things You Should Know Before Buying a Fish Finder

Understand Different Sonar Types

2D Sonar

A 2D Sonar is a traditional type available on most fish finders. It uses 83kHz and 200kHz frequencies.


CHIRP uses different sonar frequencies simultaneously to give a better image quality. It’s sometimes called a broadband sonar.

Down Imaging

Down Imaging uses a high-frequency sonar, usually between 400kHz and 800kHz. It gives you a high-resolution image of what is under your boat so that it easier to identify what exactly it might be.

Side Imaging

Side sonar is the latest feature found mostly on more advanced fish finders. It generates a high-frequency sound wave directed to the sides of the boat.

Get the Right Display Size

It’s just so much easier to see and read the detail on a display that is not only high resolution but also large enough. I would recommend getting a display at least 7″ and larger if you can afford it.

GPS Capability

Although your trolling motor might have a GPS anchor and spot marking features, it is just much more convenient to use your fish finder and mark those spots right on the chart.

Best Fish Finders Compared

These are some of the best fish finders you can buy today:

Fish FinderPriceDisplayResolutionSonarLIVE
HELIX 10 G3N CHIRP MEGA SI+ GPS$$$$10.1"1024x600CHIRP, Down Imaging,
Side Imaging
Garmin ECHOMAP 94SV$$$9"800x400CHIRP, ClearVü, SideVü
Lowrance Elite FS 9$$$9"800x480CHIRP, DownScan, SideScan
HELIX 7 CHIRP MEGA SI GPS G3N$$7"800x480CHIRP, Down Imaging, Side Imaging
Lowrance HOOK Reveal 7 TripleShot$$7"800x480CHIRP, DownScan
Garmin Striker Plus 7SV$$7"800x480CHIRP, ClearVü, SideVü
Garmin ECHOMAP UHD 64cv$$6"800x480CHIRP
Lowrance HOOK Reveal 5x SplitShot$5"800x480CHIRP, DownScan
HELIX 5 CHIRP DI GPS G2$5"800x480CHIRP, Down Imaging

Trolling Motor Fish Finder Combos

Minn Kota + Humminbird HELIX

Minn Kota has partnered with Humminbird to develop some of the most successful fish-finding combinations.

There are four Minn Kota trolling motors with built-in MEGA Down Imaging and Side Imaging, either as standard or as an optional extra: the Ultrex, the Ulterra, the Terrova, and the Fortrex.

What is great about Minn Kota’s transducers is that they are fully integrated with the lower motor section, which means there are no additional cables or connectors involved.

To fully take advantage of MEGA imaging available on the above models, you need to pair them with one of Humminbird’s HELIX fish finders. You only need to make sure it offers Down and Side Imaging as a feature.

Garmin Force + Garmin ECHOMAP

The Garmin Force is a relative newcomer to the trolling motor market and is already proving very popular with anglers.

It’s no surprise, really, considering that combined with Garmin‘s own fish finder, for example, ECHOMAP 94SV, it turns into a formidable fishing tool.

Lowrance Ghost + Lowrance ELITE

The Lowrance Ghost is another example of a trolling motor made by a marine electronics company. And it’s great, it has a new brushless motor and is super quiet.

Now, it’s no surprise the Ghost works best with Lowrance-made fish finders, such as Lowrance Elite FS 9.


A good fish finder can help give you a significant advantage, but whether it helps you find more fish also depends on your ability to use it properly.