For all seasons from the bottom to the top. The deeper structure will mostly be used as refuge during winter or cooler months of the year. That is if you are doing it for the benefit of the fish.

If you are doing it to congregate fish for better angling success put it where you want to fish and at the depth appropriate for the time of year you want to fish and for the target species.

It is good to have some at all depths, keeping in mind during winter the fish will be where the warmest water is, near the bottom.

John

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