Thermocline?

[Salmonoob]

I am fairly new to salmon fishing. I have a Lowerance elite 5 sonar unit. I was wondering if anyone can tell me if/how I can see the thermalcline with this unit? I have read all of the literature with this unit and can't find a definitive answer. Any input would be great.

[SeaCatMich]

A thermocline is a horizontal area in the water collumn where the temperature of the water is changing rapidly -- genearlly getting colder. Water has different densities at different temperatures with warmer water less dense than colder. This is true until the water gets to 39 degrees where it is the most dense but from 39 degrees to its freezing poiont at 32 degrees, water then gets less dense -- this is why ice floats on top of unfrozen water. In the winter the densest water is going to be 39* and sink to the bottom of the water collumn.

Now with that background, it is possible for a sensitive sonar unit to show the thermocline by in effect displaying the rapid density change in the water because it reflects the sound/sonar signal differently. Generally you need to turn up the gain and the sensitivity on the sonar unit to the point where you start getting clutter on the screen (looks like static on an old TV). Then when fishing you MAY see the thermocline as an area of heavier static -- sort of like a weak false bottom.

I don't have the Elite 5 but I have seen it on other units like my Raymarine unit and in the past on other fish finders -- even my old SiTex, Vexlar, and Telesonar paper graphs would show it at times.

[Nailer]

Welcome to the site Robert. Some have luck finding a thermo break by turning up the sensitivity, and looking for the dark line. I use a Fish Hawk TD and it tells me the depth every 5'. In the summer, we try to find that 50 deg. water, and fish around it.

[Salmonoob]

Thanks for the info! It is greatly appreciated. I'm chomping at the bit to start fishing.

[Priority1]

Bob, A warm

[Rascal Trophy Fishing]

Thanks for joining Robert, welcome, need anything let us know. Meanwhile, I think Ryan's post was quite true and accurate as they get. I learned something there too about density, thanks. High gain is the key for targeting thermos, for as long as the eyes hold out anyhow...lol.

[Paulywood]

I think Ryan covered it so Welcome Robert!

[Just Hook'n]

Welcome to the site Robert.

You may also have some luck with the different freqencies (50Hz vs. 200Hz).

Can't remember which, but on one of them we mark the thermocline.

[fishy1]

The 50 kz usally marks better as it uses a wider cone angle and usally used in shallower water (200 or less ) 200kz will usually mark thermo also but tend to mark less fish as it uses a smaller cone angle 8-12 degree.

[Salmonoob]

Thanks to everyone who has replied. I am looking forward to to coming spring. Last year I accidentally caught a few salmon and would like to improve my odds this year.