Sgann, The best way to tune your unit is to use the arrow key to stop your unit. Get your SI on full screen both sides. Just punch your arrow key one time and the cursor will show up. This will stop your screen from scrolling. Now here is the time to play with the setting and to observe the effects. Play with your sensitivity. Usually the deeper the water the higher the sensitivity. The shallower the less. Just know that your sensitivity setting will vary with water depth. I mostly use 455khz 90% of the time. One of the best features that I like is the sharpness option under the SI enhance tab. I like putting that on the low setting. To me that just makes the image pop. Once you have the screen tuned the way you like it maybe you'd like to navigate through the different color pallets to see which one you feel gives you the best seperation, clarity. I personally like the blue and the amber 1. Once your set hit exit and your unit will continue to scroll and scan the bottom
Mike