Grayline lets you distinguish between strong and weak echoes. It “paints” gray on targets that are stronger than a preset value. This allows you to tell the difference between a hard and soft bottom. For example, a soft, muddy or weedy bottom returns a weaker symbol which is shown with a narrow or no gray line. A hard bottom returns a strong signal which causes a wide gray line.
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Place on lake where inactive fish spend most of their time.
The bed of a stream or river.
The distance a fish moves while remaining at the same depth.