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Bottom Hardness
Is it soft mud or rocks? If you fish you need to know since fish relate to different bottom composition. Doc has 5 methods 3 high tech and 2 low tech.
We all struggle with understanding bottom hardness so it is time to add some tools fro solving the mystery.
Bottom hardness is determined by sonar with 3 sonar methods since harder bottom reflects sound (echo) better than soft bottom; the left side is harder bottom because:
- Color indicates echo strength and yellow on this palette choice relates to the strongest echo.
- Thickness of bottom band, hard bottom has a thicker band as indicated by green lines
- Second echo, only shown on the left side (white arrow)
You rarely see the 2nd echo since most people use auto range and you need a depth range set twice the depth to see it. The 2nd echo is sound reflected off the bottom which reflects off the water surface and repeats the cycle. Since sonar measures distance (depth) by time the 2nd echo takes twice a long to reach the transducer so it displays as twice the depth as the bottom.
LOW TECH METHODS
You can confirm you observations by thumping the bottom with a large sinker and your fishing rod or use an underwater camera.
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