The Fish Finder That Will Take You Into The Great Deep

The Fish Finder That Will Take You Into The Great Deep

Fish finders are great devices for locating fish underwater. An old-school fisherman will prefer the traditional way, fishing with the mystery of not knowing where to find the catch. However, professional fishermen will prefer to use fish finders on their fishing trips.

But not everyone knows how a fish finder works, nor do they know how to pick them. If you also want to become a professional fisherman, then this article will help you understand everything there is to know about this device.

What Is A Fish Finder?

A fish finder is a tool that uses sonar signals to find and report images from beneath the water’s surface. They were first developed and used during the Second World War, and they were intended for spotting enemy submarines.

Basically, it was an underwater radar system. Plus, aside from being used in fish finders, sonar technology is also found in similar aquatic applications.

Fish finder on a boat.

With a fish finder, you detect a reflected impulse of sound energy. The device will pick it up and show you a graphic image on the screen. Furthermore, a fish finder will measure the water depth and locate inanimate objects at the bottom.

Fish finders can show you fish in different ways. Just one fish, represented by an icon, or a series of arches representing a bank of fish.

Uses Of A Fish Finder

Fish finders can be used for a variety of fishing types. Here are just some of the reasons why fish finders are such a great investment:

Boat Fishing

Boat fishing is one of the most popular ways of fishing – basically, the traditional way. By using a fish finder when you go boat fishing, you’ll know where to anchor your boat to get the most fish.

This boat plus fish finder combo is also very useful because it makes you move around when needed. Freshwater fish rarely stay in the same place, so a fish finder will tell when it’s the appropriate time to move on.

Ice Fishing

Ice fishing sounds all relaxing and everything – but not when you have to drill hole after hole because the fish are not biting. That is especially unnerving when the weather seems dent on freezing your toes off.

A fish finder will tell you exactly where to “park” your devices. This way, you will not have to waste time cutting multiple holes for no reason; it will just tell you where the biggest concentration of fish is.

Shore Fishing

Let’s say that you set your tools in what you think is a good fishing spot. You prepare your tools, you take out the rod, and you throw the cast to the far right because that’s where you knew the fish would usually hang out.

Little did you know that the fish have moved to the left now because they found some shiny new corals – and they can no longer see your bait there. This is when you need a fish finder.

Types Of Fish Finders

There are several types of fish finders out there, each one with its own uses. Depending on where you plan on going fishing, you may want to go for a certain type of fish finder. Your choice will also depend on whether you’re looking for banks or bigger prey fish.

Down Imaging Fish Finders

A down imaging sonar does exactly what its name suggests: it shows you exactly what is underneath you. This type of sonar uses a thin, high frequency that produces a very detailed “image” of what is underneath you.

Down imaging fish finder.

It can come in very handy if you’re into stationary fishing and don’t like to move around a lot. It is also appropriate for deep waters since the sonar is focused on just one smaller zone underneath.

Side Imaging Fish Finders

Unlike down imaging fish finders, the side imaging ones focus down to the sides. However, since the frequency of the sound waves covers a wider area, it will not be able to reach as farther as a down imaging fish finder.

Basically, with a side imaging fish finder, you sacrifice depth for wideness. However, by going for such a tool, you will know exactly how and where to move to find the fish.

This is the opposite of a down imaging fish finder, where you can only see the fish once you are above them.

Fixed Fish Finders

Fixed fish finders are a good option for fishermen who have one boat and don’t want to bother with mounting and unmounting the device every time. They can be permanently (and securely) mounted, and the wires can be hidden away easily as well.

These types of fish finders are usually fairly large – at least compared to the portable ones. They are also the least expensive ones, considering that they have many added features.

The average fixed fish finder will have chartplotters, maps, and GPS. These will allow you to track down the fish much easier.

Portable Fish Finders

A portable fish finder, like its name suggests, is a good thing to have around if you have more than one boat – since you can move it from one to the other. Compared to fixed fish finders, these are more compact and with smaller screens.

You can easily adjust these to smaller boats such as kayaks or canoes and are also a good option if you tend to rent boats.

Handheld Fish Finders

Handheld fish finders are generally a good option if you prefer fishing from the shore. These devices are attached to the rod and cast it just like you would a bait line. The device will then start floating and provide an exact reading of what’s underneath the water surface.

Since these devices are compact, they don’t cover such a wide radius like a full-fledged fish finder would. However, the advantage is that they fit in a tackle box or a pocket, so they are a good option if you don’t like carrying a lot of stuff with you.

Rod-Mounted Fish Finders

A rod-mounted fish finder can be easily attached to the fishing rod and it connects to a transducer that you stick to the fishing line. Once the line is cast, the information will appear on the screen attached to the rod.

Parts Of A Fish Finder

Depending on its components, a fish finder can work in different ways to meet your needs. Granted, not every fish finder has the same parts, but some of them will always be present, regardless of the model.


Without the display, you can’t see where the fish are positioned. Depending on your personal preferences, a fishfinder display can be either colored or black and white.

Humminbird 410210-1 HELIX 5 CHIRP GPS G2 Fish finder


Depending on the numbers of pixels featured by a display, an image can be either high or low quality (generally, the more pixels it has, the better).


Every fish finder produces beams – but the types of beams are very different. For example, some fish finders produce only a narrow cone that doesn't scan a wide area but can go very deep.

On the other hand, there are fish finders that produce wide beams that can go across 20 meters – but can’t go deep underwater (down imaging vs. side imaging).

There are also fish finders with multiple transducers that can reach both down and on the sides – however, you’ll have to be willing to spend an extra buck or two. Most modern fish finders have specialized transducers whose beams can adjust to meet specific ends.


Logically speaking, without the GPS (global positioning system), you wouldn’t even know where to go looking for the fish. The GPS will basically take information via a satellite, and tell you the exact location so that you always reach your destination.


This is what most would say is the actual fish finder – or at least, that’s what we like to believe. The transducer picks up the data – and the display shows you what the water’s got.

In a way, you could say that the display is the TV and the transducer is the antenna that picks up the channel signal.

The display is also where the menu is, and you can use that part to adjust anything from the frequency to the zoom and the color balance.

Fish Finder Installation

So, how does one install a fishfinder? It should be easy – technically.

Find A Place For The Transducer

Figuring out where to mount the transducer is sometimes the most difficult part of installing a fish finder, but also the most important. Depending on the type of mount that you have, you might want to have it done by a professional.

A thru-hull transducer, for instance, has a more intricate wiring and will have you cutting a hole in your boat – so you might want to get some help on that. Ideally, the transducer has to be set on the transom to provide the best reading.

Look for a spot on the hull that is either in contact or completely submerged in water. Since the transducer functions on sound energy, it won’t pick up anything until it actually feels it.

Mounted fish finder.

Also, you might want to make sure that there is no turbulence near the transducer. Mount it as far away from the propeller as possible so that there is no interference with the reading.

Test The Wires

Before you mount the actual transducer, you might want to test-run the wires. If you fail to do so and only realize later on that they were not installed correctly, it will be very difficult to get past the sealant without loosening it.

If you see that the wires are too long, do not cut them. It may not affect the way the fish finder works, but it will void your warranty. Simply coil them and hide them somewhere around the main unit, far from the transducer.

Mount The Transducer

Once you found an appropriate place, glue a plastic block to it. This way, you will not have to drill directly into the boat. It’s easier to take off a glued board than to hide a big hole when you no longer need that fish finder.

Fasten the transducer there, mark the holes and then drill the screws in, and make sure that it always stays horizontally.

Mount The Fish finder

Once the transducer and the wires have been set in in place, mount the fish finder on the dashboard. Most fish finders arrive with an optional in-dash mount, which you may use to install within the dashboard.

Start Fishing

Once everything has been nicely set into place, it’s time to start fishing! If the transducer was mounted properly, then everything should work just fine.

How Does A Fish Finder Work?

Once you understand how a fish finder works, you will also understand how you have to use it. Fish finders function on sonar technology, using sound waves to show underwater objects.

The fish finder sends the sound wave through the transducer into the water. As they penetrate the water, these sound waves will form a cone (also known as “beam”).

Beam on a fish finder.

Once the waves encounter objects (animate or inanimate) within the beam range, they will send signals back to the transducer – which will further on be displayed on the screen.

How To Use A Fish Finder

Using fish finders can make any fishing trip entertaining and easy. However, if you don’t know how to use it, even the cheapest fish finder can become a headache. However, with some instructions and a little bit of practice, it should be very easy.

Understand The Display

To understand the display, you first need to read the manual carefully. Every fish finder has different features, and while some may be obvious, others may need some extra guidance. Find out where the basic information is.

If you are using a down imaging fish finder, read the screen from right to left. On the other hand, if you are using a side imaging device, read it from top to bottom.

Locate The Fish

They usually look like small patches or blobs. Arch shape or large dots will indicate larger fish, and the bottom line will indicate the bottom of the water.

Adjust The Fish finder

Once you find the fish, use the zoom button or go through the menu to get a better view of the area. This is particularly useful if you have a certain type of fish in mind that you want to catch.

If you have a colored display, you may want to adjust the palette. It will help you distinguish fish from terrain much easier. You may also want to increase the update speed as well, to receive better data.

Peak The Transducer

Sometimes, readings might be inaccurate, so you may want to peak the transducer every now and again. You can lower the sensitivity as well until the clutter is gone and you get a clear reading.

How you use a fish finder depends on the model as well, which is why you always need to read the instruction manual. If you buy the best fish finder under 500, for example, it might have more options than a less expensive one.


The name of the manufacturer might tell you a lot about the product that you are getting.

Different fish finders.

How long has that company been in business? Is it well-respected? Do they have the best fish finder reviews on the market? Knowing this will tell you whether your purchase is worthwhile or not.


Humminbird is one of the most popular brands of fish finders. They provide devices that work from all angles, offering you many options for whatever type of water that you choose to fish in: oceans, lakes, rivers, etc.

Every recent Humminbird fish finder will also have intuitive navigation, integrated autopilot, and high-definition lake maps. They are usually a great option to have around because they don’t require much interference.


A Deeper fish finder can be used on any fishing type – going from boat to shore and ice fishing. They focus on wireless technology, making the fishing process less of a hassle to deal with.

Newer ones can also be connected to smartphones, making it very easy for you to stay connected even though you are outside wireless areas.


Lowrance focuses on easy-to-use fish finders, mostly with autopilot and auto-setting. They’re usually the main choices for beginner fishermen that are still getting the hang of catching fish.

A Lowrance fish finder can be used on both saltwater and freshwater, usually covering a wide area – especially with the newer models.


Garmin manufactures a lot of accessories meant to be used for outdoor activities. Their technology includes built-in GPS and CHIRP sonars.

A Garmin fish finder can generally be added to anything from a fishing boat to a kayak or a canoe.  


Hawkeye brings portability in your hands. So, if you are looking for ease of use and devices that don’t occupy half your boat space, you can go for a Hawkeye fish finder.

They also make the best fish finder for the money, so if you are looking for something effective yet qualitative, you can give them a try.


Like with every electronic device, a fish finder needs care; however, the wrong type of care may easily destroy something for which you paid a lot of money.

Cleaning The Screen

One of the most important fish finder parts that needs to be cleaned is the screen. Keep in mind that the display is like a flat-screen TV – very prone to scratches and damage, so you might want to be careful how you handle it.

Fish finder maintenance.

To prevent the fading of visibility from the screen, you shouldn’t allow the formation of smudges and spots. These can appear for many reasons, from rain to splashes and waves.

You may want to dry your fish finder as quickly as possible in the event that it gets wet. Indeed, these devices are water resistant. Still, if you let the water dry on the screen, it might leave unsightly smudges and spots – and it won’t be easy to clean those up.

If you have a more expensive fish finder, it’s very likely that it also has an Anti-Reflective coating. This will help you see better on the screen, but it is also sensitive to most traditional cleaners – and therefore, you have to be careful.

Under no circumstances should you use abrasives, ammonia or alcohol-based cleaners to care for your screen. Not only will it scour off the Anti-Reflective coating, but it may also completely dissolve it.

Maintaining Your Transducer

To clean your transducer, you need to keep it clear of petroleum and growth residue. Use a soft cloth and some detergent – but make sure it’s a mild one. You may also want to avoid using brushes with stiff bristles, since it may scratch the surface of the transducer.

Unless you have a multi-element transducer, avoid using the fish finder if it has not been submerged in water. If the cooling effect of water is not present, these devices may easily overheat, resulting in damage to the internal structure.

Final Thoughts

Having a fish finder on board can make the life of every fisherman easier. Gone are the days when you would have to wander aimlessly in random spots, praying to the almighty water god to send fish your way.

Now, with just the touch of a screen, you can get a fish finder that will show you exactly where you should fish. Therefore, instead of coming home with some little fish, you’ll be coming with a trophy.

FIshfinder with GPS.

If you want to discover the best fish finder, then you may want to throw a glance at our buying guide. We’ve listed a few important features to consider, as well as some models that were deeply appreciated by many fishing fans.

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