I wrote recently about my first trip to Finland with Rock and Lake in 2016, a lot of fish were caught in beautiful surroundings and a truly wonderful family holiday was had. Whilst I failed to connect with any of the larger pike that Lake Puula is reputed to hold, it had been my first experience boat fishing big waters for predators and I loved every minute of it. A return trip was promptly booked for summer 2017.
Thinking about the trip on my return to Moscow, I was intrigued to understand why numerous pike had been caught blindly trailing (or trolling) my lures behind the boat in open water. There must have been some underwater features that attracted the fish to those areas. If only I could see beneath the surface, perhaps next time around I would be able to find the haunts of some slightly bigger specimens.
Inspired by many YouTube videos of big water pike fishing and following a great deal of online research (as well as soul searching – see further below), I took the plunge and purchased a Deeper 3.0 Smart Fishfinder from Glasgow Angling Centre and a Flexible Arm Mount from Tackle UK. Together, I felt these two products could give me the subaquatic ‘eyes’ I needed.


As ever with these tackle dealers the purchased items arrived promptly and I could not wait to get to grips with them. Deeper have a great website (with lots of useful materials as well as access to an online community of Deeper users). I had hoped to devote some time to reading in prior to the trip and even testing the devices using some of the rowing boats available for hire in the city parks of Moscow. Unfortunately however, due to work commitments, I was unable to get either product out of its package in advance, which meant they would have to be tested ‘in the field’.
Thankfully, the Deeper fishfinder is designed for technophobe/time poor anglers like me and is very easy to use. Basically you charge it up, download the app and you are good to go. Simply tether the fully-charged fishfinder to the boat, drop it into the water and trail it along with you. As soon as it contacts water, it connects with your phone via Bluetooth and you start getting an underwater picture – water temperature, depth, bottom structure and, most importantly, fish. It is that simple.
As for the Deeper flexible arm mount this was much less impressive. I had read that the Bluetooth connection between the fishfinder and your phone could be intermittent in rough water and the steadying support of the arm mount helps secure the connection. I actually found it was the complete opposite. My first few outings with the arm mount saw connectivity constantly being lost as the droopy arm mount would gradually submerge the usually buoyant fishfinder. This in turn would result in either a lost signal or, if the signal were not lost, the fishfinder constantly detecting the arm mount itself as a ‘fish’. The final straw came when the bolt that fastens the arm mount to the boat broke after two days’ use. I reverted to just tethering the fishfinder and letting it float alongside the boat. Bluetooth connection was barely lost again for the rest of the trip.
Over the course of the week I got to know some of the other features of the fishfinder, the most interesting of which was the GPS tracking. This allows you to gradually ‘colour in’ the water you are fishing creating a topographic (contour) map of the areas you have covered.


As mentioned above, I did hesitate over investing in a fishfinder/sonar: Was I cheating? Should I rely on my own watercraft and instinct rather than technology? Would I spend too much time afloat staring at my phone (which I already do too much of in everyday life) instead of taking in the natural surroundings?
Following my first week afloat with the Deeper fishfinder, I can safely say that I have no regrets and my conscience is clear. In truth, having some level of underwater visibility is the only way to effectively fish big waters, especially as a visiting angler with limited time. Whilst you do end up looking at your phone a bit more when out fishing, it was not too intrusive. If you place your phone somewhere convenient you can fish or row with your head up and still enjoy the scenery with only the occasional glance down at the screen.
Does the Deeper fishfinder work? Yes, undoubtedly.
Whilst my fishing buddy, Andy, and I did have some banter about it just been a gimmick that randomly scrolls a fictional underwater scene, we both concluded it was accurate and increased our catch rate. Numerous times we would hook up shortly after seeing schools of bait fish on the screen, and it certainly helped us identify features to concentrate our efforts on.
Finally, it is easy and fun to use. I am really looking forward to taking it out again on some U.K. waters this winter and getting to grips with more of the features – maybe it will help me find my first twenty pound pike.

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