Garmin Fish Finder Side Scan: How to Set Up and Read the Image

Updated November 2026

A garmin fish finder side scan unit shows you the bottom and structure on both sides of your boat, not just directly underneath it. Once you know how to set it up and read the image, you can find humps, wrecks, weed edges and bait schools without running over them first. This guide covers setup, the settings that matter, and how to interpret what you see on screen.

How Garmin Side Scan Works

Side scan sends fan-shaped beams out to the left and right of the transducer, usually mounted on the transom or trolling motor. The returning echoes build a picture of the bottom as the boat moves forward. Hard surfaces like rock and wood return strong signals and appear bright, while soft mud and sand show up darker. For a broader primer on the technology, see Side Scan Sonar Fish Finder: How It Works and How to Use It (2026).

Shopping for one? See our guide: 7 Best Side Scan Fish Finder Models for Every Angler (2026).

Setting Up Your Garmin Side Scan Unit

Installation determines how clean your image will be. Mount the transducer so it sits in clean water, free of air bubbles, and parallel to the waterline. Enter the transducer type in the setup menu, then confirm the unit is detecting side scan returns before you leave the dock.

1. Confirm the transducer is fully submerged at speed and hasn’t been fouled by weeds or debris.
2. Select the side scan transducer in the sonar setup menu so the correct channels are active.
3. Set the range to a starting point of about 60 to 80 feet in shallow water, adjusting as you move into deeper areas.
4. Run a test pass over a known feature to verify the image is sharp on both sides.

Key Settings for a Clear Side Scan Image

Most poor images come from gain or range settings rather than the hardware itself. Auto gain is a good default for most anglers, but manual adjustments help when you need more detail in specific depths.

Setting	What it does	Typical adjustment
Range	Sets how far each side is scanned	Shorter range for sharper detail
Gain	Controls signal sensitivity	Raise if the image is faint, lower if it is washed out
Color palette	Changes how hard and soft bottoms appear	Use high contrast in bright sun
Boat speed	Affects how stretched the image looks	Slow down for better resolution

Reading the Side Scan Image

Learning to read the image takes a few trips, but the basics are straightforward. Bright, sharp edges usually mean rock, debris or a hard structure edge. Dark, smooth zones point to mud or sand. Shadows behind an object show its height, which helps you tell a log from a rock pile. Fish marks appear as small clusters or arcs above the bottom, and they often look different from bottom structure because they show up in the water column.

Pay attention to the transitions. Edges between hard and soft bottom are where many species feed, so slow down and make repeated passes over them. Owners often report that tracking the same contour from two directions helps confirm whether a feature is real or an artifact of boat speed.

Common Mistakes

• Running too fast, which stretches the image and hides detail.
• Leaving range set to maximum in shallow water, which lowers resolution.
• Mounting the transducer near the motor or in turbulent flow, causing bubble interference.
• Confusing fish arches with bottom debris; cross-check with a second pass.
• Ignoring the difference between side scan and down imaging. Each shows the water differently, and the Garmin LiveScope Fish Finder guide explains how they complement each other.

Recommended Gear

• Garmin Striker series transducer mount gives a stable, adjustable mounting point so the transducer stays level at speed. View on Amazon
• Transom mount bracket helps keep the transducer out of prop wash and reduces bubble interference. View on Amazon
• Transducer cleaning brush removes algae and weed buildup that can dull your returns between trips. View on Amazon

FAQ

Can I use a garmin fish finder side scan on a kayak?

Yes, as long as the transducer mount is compatible with your kayak’s hull or trolling motor setup. Many kayak anglers choose a compact unit with a clamp or transom bracket. Check the manufacturer’s mounting specifications before buying.

Why does my side scan image look blurry?

Blurry images usually come from excessive boat speed, a range setting that is too long, or a transducer that is not fully submerged. Slow down, shorten the range and check the mount for air bubbles.

Does side scan replace down imaging?

No. Side scan covers the area to the sides of the boat, while down imaging gives a detailed view directly below. Most anglers use both to build a complete picture of the bottom and the fish around it.

Conclusion

A garmin fish finder side scan gives you a wider view of the bottom than any single-beam sounder, which means fewer blind guesses and more productive passes. Set the transducer correctly, dial in range and gain, and practice reading hard and soft bottom edges. With a few trips of experience, you will start finding structure and fish you would have missed before.

Related reading

• 6 Best Fish Finders with Side Scan: Top Picks Compared (2026)
• Side Scanning Sonar Fish Finder: How It Works and How to Use It (2026)
• Side Scanning Fish Finder: How It Works and How to Use One (2026)

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