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I see this so often on our fish finder (in the attached picture) where all the fish are lined up vertically like this. What is actually going on under the surface? Do fish actually hang out vertically like this? If anything I would expect them to hang out horizontally at the temp break. Could it be the sonar bouncing back and forth between a couple fish and making multiple marks? Just curious because I see it so often. Does anyone else have this and know what's going on?

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Given what I would consider to be a high amount of clutter/noise on your screen, my thought is that you are getting multiple readings of around 2 or 3 fish. Hard to really see on the picture but look for the marks being at depth multipliers -- highest good mark at 25' and another at 50, next highest at 30 with second at 60, 45/90... If gain is real high you could even get triple on shallow fish 30/60/90. The only reason I would have the gain/sensitivity that high with today's electronics would be if looking for small fish such as a school of perch near bottom in deeper water.

Basically the same thing as setting your depth range to 300' with the real bottom in 90'. If the gain or sensitivity is set too high you will see a second bottom at 180 and if it is real high, a third at 270.

I set my gain so that it is just lower than what is needed to get the second reading of bottom. Set the max depth to a little over 2x the actual depth and increase the gain until the double bottom snows up and then reduce it until it disappears. Then set the max to a range that will not show the 2nd bottom echo -- ie: bottom is 120 then max is 150.

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Given what I would consider to be a high amount of clutter/noise on your screen, my thought is that you are getting multiple readings of around 2 or 3 fish. Hard to really see on the picture but look for the marks being at depth multipliers -- highest good mark at 25' and another at 50, next highest at 30 with second at 60, 45/90... If gain is real high you could even get triple on shallow fish 30/60/90. The only reason I would have the gain/sensitivity that high with today's electronics would be if looking for small fish such as a school of perch near bottom in deeper water.

Basically the same thing as setting your depth range to 300' with the real bottom in 90'. If the gain or sensitivity is set too high you will see a second bottom at 180 and if it is real high, a third at 270.

I set my gain so that it is just lower than what is needed to get the second reading of bottom. Set the max depth to a little over 2x the actual depth and increase the gain until the double bottom snows up and then reduce it until it disappears. Then set the max to a range that will not show the 2nd bottom echo -- ie: bottom is 120 then max is 150.

have to agree with him. it looks like you have your gain set to high. you should have a clear screen if the gain is right unless you getting electrical noise on your screen.

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Given what I would consider to be a high amount of clutter/noise on your screen, my thought is that you are getting multiple readings of around 2 or 3 fish. Hard to really see on the picture but look for the marks being at depth multipliers -- highest good mark at 25' and another at 50, next highest at 30 with second at 60, 45/90... If gain is real high you could even get triple on shallow fish 30/60/90. The only reason I would have the gain/sensitivity that high with today's electronics would be if looking for small fish such as a school of perch near bottom in deeper water.

Basically the same thing as setting your depth range to 300' with the real bottom in 90'. If the gain or sensitivity is set too high you will see a second bottom at 180 and if it is real high, a third at 270.

I set my gain so that it is just lower than what is needed to get the second reading of bottom. Set the max depth to a little over 2x the actual depth and increase the gain until the double bottom snows up and then reduce it until it disappears. Then set the max to a range that will not show the 2nd bottom echo -- ie: bottom is 120 then max is 150.

I read an article several years ago that the proper gain setting was to just get the third echo to register. Set depth at least 3X the actual depth then increase/decrease gain to get that result. Surface clutter/noise reduction settings should be as minimal as possible.

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Holy high gain Batman looks like we need to use depth charges LOL. That reminds me of a friend of mines fishfinder he had every gain maxed out. Plus he had fish ID on max and the thing rang like a monkey on a piano til I could no longer take it and reset it for him.

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I read an article several years ago that the proper gain setting was to just get the third echo to register. Set depth at least 3X the actual depth then increase/decrease gain to get that result. Surface clutter/noise reduction settings should be as minimal as possible.

10 years ago I would have agreed. Most newer units are much more efficient though and don't require that much gain.

I don't use Lowrance (and haven't in many years) but from what I have seen, they have both power/gain settings and sensitivity plus lots of other settings. The one setting I wouldn't ever rely on is automatic. Put it in manual mode and then start tweaking things.

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Just curious Ryan, why do you set a max range just above what your expecting to fish in? I always use the auto range. Does that have a negative effect I don't know about?

Not really negative, I just don't like it jumping between scales a lot. Auto range is great if the bottom isn't moving around a lot. Much of the time I am also usually fishing in/out (E/W) to try to find fish in different depths of water and with auto range it has it moving all over the place. Same thing when I'm weaving a shelf like off Ludington up to Frankfort, when going from 70 to 120 I prefer to have the bottom set on 150 rather than having it jump around. Another thing is that I often fish in deeper water (250'+) but the fish are typically not that deep. So I will have my main display showing a range in the water and not the whole column... say 30' to 150 if the downtemp allows me to eliminate that water. I typically don't worry about the top 20' of water in summer as far as marks -- but will put some board rods up there for steelhead if I have enough people onboard.

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10 years ago I would have agreed. Most newer units are much more efficient though and don't require that much gain.

I don't use Lowrance (and haven't in many years) but from what I have seen, they have both power/gain settings and sensitivity plus lots of other settings. The one setting I wouldn't ever rely on is automatic. Put it in manual mode and then start tweaking things.

I thought about that after I posted. The article was several years ago and the electronics advance year by year so that advice may be outdated. It would be good to get another take on the subject by someone in the industry as opposed to a bunch of opinions.

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Just curious Ryan, why do you set a max range just above what your expecting to fish in? I always use the auto range. Does that have a negative effect I don't know about?

I have only owned Lowrance, and use auto range and it doesn't jump around much, nor does it affect performance. When I say gain, I mean sensitivity. ( thought they were the same). I split my screen and zoom in on water column I want on half. The deeper and the cleaner the water, the higher sensitivity can be set.

Sent from my XT1254 using Tapatalk

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When targeting kings that are not bottom oriented I very rarely have my finder locked on bottom. If the fish I am targeting in open water are say from fifty to one hundred feet down I will lock bottom at 150 feet if I am over say 300 feet of water. there is no reason to be looking at the bottom 150 feet of water. This will give you a much better look at the area you are targeting. Likewise if the fish are deep like they have been this year (80 to 150 down. I will also lock the top out as well. On my trips this year there have not been any fish in the top 50 feet, so I will lock the finder at say 40 feet at the top and 180 at the bottom. Just to have more of my screen in the target area.

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