Basics for Ice Fishing (Deeper PRO and CHIRP models)

Make sure your sonar is water-proof. If you are using Deeper CHIRP or PRO models, always make sure the top cover of your Deeper is attached properly. ‘Water’ and ‘Proof’ marks should align perfectly.

  1. Put the cap on the Deeper case by aligning the waterproof marks, but don't screw it just yet;
  2. Carefully screw counterclockwise till it dips in;
  3. As soon as it dips, start screwing clockwise. Close it tightly until the “water proof” marks align perfectly.

Initial Connection:

  1. Put your Deeper Sonar in the ice hole. Make sure the ice hole is completely clean from ice and snow.
  2. Go to the Wi-Fi connections (settings) of your smartphone. In the list of available Wi-Fi connections, find your Deeper Sonar and connect to it. If it asks for a password – it’s 12345678
  3. Then, open the Fish Deeper app and connect to your sonar. Make sure that the app is granted access to determine your location, and GPS is enabled on your phone.
  4. Enable Ice fishing mode in the app.

The Deeper PRO/PRO+ and CHIRP are both suitable for ice fishing – they operate at temperatures down to -20°C / -4°F. The Deeper START is not designed for ice fishing – it operates at temperatures down to 0°C / 32°F.

When you are using your Deeper for ice fishing, enable the Ice Fishing Mode (Settings > Ice Fishing).

Enabling this setting gives you the best display options for ice fishing and automatically configures the best sonar settings for ice fishing.

Drill and Drop

Once you have drilled your ice hole, you can simply drop your Deeper Sonar in to start scanning. It is not necessary to attach a line to your Deeper, although you may choose to do so for easy removal from the ice hole – in this case, use the top attachment point for attaching a line. Your Deeper will switch on automatically once in the water, then sync your smartphone and it will begin scanning. Please note, in very cold conditions ice can build up on the two electric nodes on the bottom of your Deeper, and this can prevent the device from switching on. Simply clean off the ice from the two nodes and drop your Deeper back into the ice hole and this should solve the problem.


Ice Thickness

Deeper Sonars float on the surface of the water (rather than being submerged like other ice flashers). This means that when the ice is very thick, the sonar may not scan correctly because the sonar cone hits the sides of the ice hole and the sonar pulses are reflected back. To avoid this, there are two things you can do:

  • Drill larger ice holes if the ice is very thick. This will reduce the chance of the sonar cone hitting the side of the ice hole;
  • Ensure your Deeper Sonar is positioned directly in the center of the ice hole;
  • Drill vertical ice holes, keep the ice hole clean from ice and snow;
  • If you are using CHIRP+, make sure you are using Narrow CHIRP beam (7°).



You should be aware that in temperatures below freezing, the battery of both your Deeper device and your smartphone / tablet will drain faster. Here’s what you can do to manage this:

Deeper Battery

  1. Ensure the battery is fully charged before any trip.
  2. Remove your Deeper fish finder from the water when you are not using it, and keep it insulated (for example, inside the neoprene pouch that comes with the Deeper, or inside your pocket).
  3. Have a power bank on hand to charge your Deeper during your trip. Please remember that the Lithium ion battery in your Deeper can only be charged in temperatures of 3°C / 37.4°F or higher (when you start charging your Deeper, a blue LED will show if the conditions are too cold for charging). Charging in your car or in a warmed ice shanty are good options.
  4. If you are using Deeper CHIRP model, you can enable Low power mode to conserve battery.

Smartphone Battery

  1. Ensure your smartphone / tablet is fully charged before your trip.
  2. Use the Deeper Winter Smartphone Case to insulate your smartphone while using it, thus preserving its battery life.
  3. Have a power bank on hand to charge your smartphone during your trip.

Find the right spot

Judging if you are fishing at the right spot is straightforward. Just drop your Deeper into the ice hole. The depth will be shown in the center of the circular flasher display and in the top right corner of the display screen. You can also look for vegetation using the traditional sonar section of the display screen, where it will be shown in green. This information about vegetation and depth can help you to decide if this is a good place to fish.

Drilling a grid of ice holes is also an effective approach. Once you have drilled your grid, you can drop your Deeper into each hole to monitor how the depth changes and locate the best spot.

Finally, if you have been able to map an area in summer using your boat / kayak, or from the shore with your Deeper PRO+ or CHIRP+, you can use the map to return to the best spots in hard water season.


Marking fish and tracking your lure

The ice fishing display on the Deeper App gives you a number of ways to locate fish, track your lure and see how the fish respond to your actions. On the left-hand side is the Traditional Circular Flasher display, in the middle right-hand side there is the Sonar Display, and on the far right-hand side there is the Vertical Flasher.

- Sonar display: This is the same as the Standard Display for scanning from the shore. The blue band shown at the top is the ice, the orange band lower down is the bottom, and any objects shown in between are either fish or you lure. You can adjust the sensitivity of this display in the left-hand menu and change the color palette to day or night palettes (Settings > Sonar > Screen Color Mode).

Traditional Circular Flasher: This display is exactly like a traditional ice flasher. In the center you will see the depth and surface water temperature displayed. Around the side is the actual flasher. At the very top, you will see a band of blue/grey color – this is the ice itself. Then follow the display clockwise until you see a brown/orange band of color – this is the bottom. Anything displayed in between the ice and the bottom will be either your lure or a fish. These will show as bands of green/yellow color.

- Vertical Flasher: On the right-hand side of the display screen is the Vertical Flasher. Here all the sonar readings are shown in white, on a black background. At the very top you will see a blob of white that is moving slightly – this is the ice. Then at the bottom of the display there will be a thick white shape that tapers off at the bottom – this is the bottom. Any lure, jig or fish will be shown in between these two as moving white bands. The size and thickness of the band gives you an indication of the size of the object.


Map and GPS Ice Hole Marking

The Ice Fishing display also has a mapping function (to ensure this function works, make sure are a registered user and have downloaded the Offline Maps for your state or country). You will see a map icon on the left-hand side of the display. If you click this, a map will open showing your current location. When you drop your Deeper into an ice hole, that location will automatically be marked onto your map and saved. As you fish more ice holes, these will also be added to your map. If you click on one of these locations, it will automatically show you the depth at that spot.

Please note the Fish Deeper App uses your smartphone or tablet’s GPS for this function (no internet connection is required). For accurate location marking, please make sure your smartphone is within 3 ft / 1m of the ice hole the first time you drop your Deeper in.


Fishing multiple ice holes

With their wireless range of 330ft, the Deeper PRO/PRO+/CHIRP+ enable you to monitor an ice hole at distance. This means you can be fishing one ice hole and have your Deeper in another, so you can monitor the activity in that hole as well.


Sonar interference from other flashers

If there are other ice flashers being used close to your ice hole, you may experience sonar interference from these units. This can affect the accuracy of the sonar readings you get from your Deeper. When possible, try to keep as much distance as possible from other ice flasher users.