Selecting the Right Sonar Unit for Your Fishing Needs and Pocketbook

By Chris Grocholski
February 6, 2006

Pixels, resolution, hyper scroll, cone angles, watts of power, color line, and many other features can make just about anybody’s head spin when trying to decide what sonar works best for your fishing needs. Not only are there many technical terms that go along with finding the right "fish finder," but there is still the age-old deciding factor that makes the final decision 7 out of 10 times, and that is price. “Why does this unit cost $700, and this unit only cost $150”? This is a question that I can honestly say I hear at least 10 or 20 times a week, but after reading this article, maybe we can shed a bit of light on the subject of sonar and fish finders.

A Dash of Color Sonars

Well, when trying to answer a question we need to ask it first! So, why doesn’t every unit cost $700 and not $150? There are actually many different reasons. The first and most obvious is probably color screens. When you look at a color screen versus a common monochrome/black-and-white, you obviously notice the reds, greens, yellows, and blues, but that shouldn’t be the first thing we notice. We should see how the reflection from lights and sunlight do not affect how the screen looks, however, when you look at a standard black and white screen, those same lights and sunlight almost make the screen disappear.

Color fish finders have also made it possible for fisherman to see types of bottom changes: muddy, weedy, and rocky bottoms can be represented on a color fish finder by a simple change in color. For example, the Lowrance LCX-20C color fish finder can tell a walleye fisherman when a rocky wing dam stops and where the long sand flat starts, and at the same time can tell a crappie fisherman where the borders are to a stump field just by what sonar function they are using. A unit with a standard black and white screen can only do so by making lighter or darker shades of gray, and if you don’t know exactly what to look for you might not be catching fish. The advancement of color to the fish finder's world has not only driven up costs, but also, and more importantly, opened up vast new abilities to what your finder can do.

Black and White Sonars

Now that we have made a distinction of color versus black-and-white, we should talk a bit more about the differences between black and white units themselves. Again, we can ask the same question. Why does this black and white unit cost $400, and this one only $150? That question isn’t as easy to answer, because one unit can look ALMOST the same. To find the difference between black and white units can be a bit more technical. Things like pixel counts, watts of power, or fish reveal can be things that can make units have price point differences. For example, the Eagle Cuda 128, 168, and 168ex, and the Hummingbird Piranha 10 and 20, are all units that will be priced around $80 to $130. These units that are very simple to use, but at the same time, do not offer much to the fisherman. They are units that have lower screen resolution due to their low pixel counts, which are 128 and 168 respectively. I like to think of them as good units that work well attached to a trolling motor, so a fisherman can know exactly what depth they are fishing in while they are running their trolling motor.


Eagle units, such as the Fishmark 320, Fishmark 480, Hummingbird’s Fish Finder 525, 535, and 565 ($170 to $200), are units that are 480x320 pixels, and in the case of Hummingbird’s, 565x640 pixels. The increase in pixels will not only help to better display the bottom of the area you are fishing, but will also help you find fish that are holding tightly to structure.

Units, for example the Lowrance X-125 and X-135, and some of Hummingbird’s newest 700-series units, are units that offer the same pixel counts as some of their counterparts like the units mentioned before, but they offer a very significant increase in features, like watts of power, utilizing the flasher screen, and a lower separation measurement. The higher the watts of power a unit has, the easier it will be to pick out individual fish. For example, the X-135 has a separation of ½ inch, and it can tell between bottom and a fish as long as they are up to ½ inch apart. Keep in mind that when features and power goes up, so does the price, and the X-125 and X-135 will run you $299 to $399 respectfully.

So which Models do You Recommend?

The Hummingbird 565 is probably one of my most recommended units to customers in the black-and-white/monochrome area. Not only does it utilize the high 640 vertical pixel count, but it also gives fishermen the dual beam transducer angle of 20 and 60 degrees. The unit not only can show you fish, but it can tell you approximately how far they are from the boat, if they are right under the boat in the 20-degree cone (or a bit wider) and in the remaining outside 40-degree cone.

When it comes to color, the unit that I'd recommend to my customers would be the Lowrance X-102. Again, the high visible color display, 2400 watts of power, and the ability to detect bottom changes from rock to soft weedy bottoms using the "bottom color tracking" feature are just a few features that make the X-102 my top choice when it comes to color sonars.