Burbot are a predatory species. In some places the supreme predators. They will feed actively in all water columns, and eat just about anything they can swallow. But they are opportunists as well, and eat dead things frequently, hey its a free meal right.. They have a tremendous sense of smell which I feel contributes to their tendency to take just about anything. I've always noticed that the fresher the bait the better the bite. They do however spend most of their time towards the bottom Of the water column and that's why a sit and wait approach is among my favorite open water tactics, Maybe because that gives me a better chance to sit around a campfire roasting dogs and drinking beer. Under the Hard Water jigging is a favorite tactic although you can still go with the sit and wait approach. Take two rods and try both.
Hope that helps a little