Fish arcs

I recently istalled a Garmin Striker 4 Plus CV on my yak using the duct seal in hull method. Instead of getting arcs for fish I'm getting "lines of blobs" (for lack of better words). Sorry, no pic. I left phone in the car. I was very careful not to get air bubbles in the duct seal. I even took a piece of clean, polished steel and rolled it out on a granite surface plate like dough. I read somewhere that in shallow water I won't get arcs, but I was in 8 fow. The down imaging and the bottom structure on the sonar looked reasonable, but anything in the water column was a long, thick line. Do I have the duct seal too thick between the hull and transducer or is this actually a depth issue? It's hard for me to believe that the marks I was getting were because of not enough depth. I'm switching to a ram mount anyway but curious if tje depth issue I read about is really a thing in 8 fow. Also worth mentioning I was moving anywhere from 0 to 1.5 mph. Thanks for any ideas.

You won't get an arch when not moving or moving very slow.

x2. What he said.

I use the fish ID instead
Here is a top that produced some nice ones a couple weeks ago
Attachment 297971


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