Hello All, Posting here and hoping to get feedback good or bad on this fishfinder that I have installed in my boat. Have gone offshore only once since and the unit tracks bottom OK in depths to 140-150 fa. so I,m not worried about that. My concerns are toward actually seeing tuna marks out at the buoys that are in really deep water 500-900 fa. The tuna usually hang out at 30-60 fa. but I'd like to be prepared to find them when they return in the spring. We pop little bags of chum attached to our baited lines and knowing where the fish are is important.Mahalo for any help.