Fish Finder FAQs

The latest in smart technology, designed exclusively for fishermen who want to minimise dormant time spent out on the water and really hone their craft. A fish finder is a piece of technology which uses pulses of sound energy to locate fish underwater. Confused? You’re not alone – the very technology behind fish finders often raises more questions than answers among buyers. So, in a bid to make this technology more accessible and to help you determine whether a fish finder is a good investment, we’ve created a round-up of some of the most commonly asked questions on the market.

What is a fish finder?

Fish finders are technological devices that are fitted to boats to monitor the movement of large bodies underwater – capable of identifying schools of fish, underwater debris and wreckages as well as depth of a body of water (be it the ocean, a river bed, canal or lake). When used by commercial trawlers and fishermen, these devices form an integral part of an efficient fishing session. These kinds of users will be relying on fish finders with a high wattage of power in order to create and transmit waves powerful enough to reach the bottom of a large and open body of water. Hobby fishermen, meanwhile, can generally use a lower wattage fish finder which provides sufficient power for smaller lakes and reservoirs. Whatever kind of fisherman you are, a hobbyist or a more serious angler, a fish finder alleviates the hassle of locating fish and lets you jump straight into catching them. And here at Hudson Marine, we offer a range of models each boasting their own set of benefits and features.

How does a fish finder work?

The devices use electrical impulses which originate in a transmitter and are transformed into sound waves before being released into the water. These waves travel through water and when they meet something they reflect the signal back – allowing the fish finder to read how large the object or mass is, how deep it is and where it is. Modern innovation means that fish finders are also now capable of distinguishing between different obstacles or mass bodies in the water and can identify the exact location of a school of fish as it moves past the boat.

How do you read a fish finder?

Fish finders are fitted with a screen which depending on your chosen brand and model presents a complex and sophisticated outline of the water bed below you, its depth, any obstacles or debris and the location of fish. When it comes to reading a fish finder, most devices utilise the concept of a fish being presented as an arch – thus indicating the movement of the fish and allowing your device to plot the fish before it passes underneath your boat, when it is right underneath your boat and when it has passed out the other side. The smaller the arch, the smaller the fish – however, it is important to understand that an elongated arch does not mean the fish is bigger, simply that it is moving more slowly. In seeking a large fish, what matters most is the prominence of the arch and its height. Some things to note when learning how to read a fish finder include:

A half arch may indicate that a fish has swum part way across your SONAR range but has not been fully immersed in the device’s area of monitoring
The depth finder built into your device can also provide information as to the water temperature – which for skilled fishermen will give you a better idea of which fish may be residing in that area
Vertical lines across the screen mean you are passing over an area of dense vegetation
A V-shaped dip along the bottom waterbed tracker means you are passing over an area of depression
Different models offer different ways of interpreting information, for example some brands utilise colour technology while others keep it simple with black and white screen.

How do you read a Garmin fish finder?

When it comes to reading a Garmin fish finder, as ever the quality of Garmin’s location technology optimises the experience and combined with the sophisticated display, Garmin fish finder owners can even create their own maps for future use and receive near-photographic quality images of the water bed which lies below them. In addition to being portable and easy to use, Garmin fish finders are renowned for using three types of SONAR to easily distinguish between fish and other miscellaneous underwater objects and use a high frequency to provide you with water depth information quickly.

Installing a fish finder:

How to install a fish finder on a fibreglass boat? If you want to install your fish finder on a fibreglass boat, the first thing you need to do is identify the best location for your device. It’s then a case of drilling holes in the right place for the mount and wires – keeping the wires sealed at all times while enabling access to power your device. The fish finder needs to be located somewhere that is easy to read from the cockpit without the structure of the boat impeding on the reading. How to install a fish finder on an aluminium boat? For an aluminium boat, you will need a fish finder that comes with a transducer, as this is what enables your device to read the water effectively. The transducer, in this case, is what will read the water – transmitting the data to your device for optimum readability. The best way to install your fish finder on an aluminium boat is to install the transducer to the bottom of the boat’s trolling motor, just beneath the surface of the water. The cable then needs to run from the transducer to your fish finder device, which should be placed in a location that is easy to access and read. Which fish finder is best for a kayak? The best fish finder for a kayak is one which can be mounted onto your boat (or which is portable for an inflatable kayak) because it allows for easy reading on the move. For most kayakers, the best fish finder is one which is very visual in its readings – with a clear display which allows the user to differentiate between different fish beneath them while also reading and understanding the landscape below. The Garmin Striker range of fish finders are particularly popular for kayakers because they combine high level scanning quality with the GPS tracker for ease of navigation and users can even build and save their own maps for future use.

How do I Identify fish through a fish finder?

The main thing you need to know about using a fish finder is that every model is different and that, prior to using your device, you should familiarise yourself with the Fish ID system. In a fish finder that uses arches to display fish, the thicker the arch is the bigger the fish it represents. For those who are fishing for trophy catches, this is one of the main points that you will focus on. Meanwhile, much smaller fish will be presented as small arches and sometimes even dots depending on the movement and size of the group in full. Alternatively, if you have a more sophisticated model with a built-in Fish ID system then you may find that the device does a lot of the work for you – presenting images of fish which have been converted by your device and the SONAR technology it uses to read the water. Showing you everything from the length and size to the shape of the fish, this can optimise your experience and make finding the perfect fish even easier.

Is a fish finder worth it?

If you enjoy fishing, either as a light hobby or as part of a more serious angling club, a fish finder can not only help you to understand the area you are fishing in, but it also allows you to pinpoint the location of different fish and – as you familiarise yourself with your device – even help you recognise which fish are located around your boat. Our collection of fish finders all boast their own unique selling points and features, with three core ranges available at Hudson Marine. For more advice and guidance on selecting the right fish finder for you, whatever your needs or preferences, don’t hesitate to get in touch with the team – or check out our blog page for more information.