Brian,
Sawtooth and Lucky give great advice. Sometimes, we have two downriggers out, and the third pole with lead core gets all the action. This is often true even in the heat of the summer, but usually early in the A.M., before they drop. You will love downriggers; they are, in my mind, a necessity, and will greatly increase your catch rate. I know some will disagree with this next bit of advice, but I strongly recommend the Penn downriggers. I fish a lot on the ocean for salmon, and on the west coast, you will find that Penns dominate. They never seem to break down, and they have HUGE numbers to indicate depth. It can be difficult early in the morning and later in the evening to read depths on a small readout. Unfortunately, no one around here carries them. They can be ordered easily on the internet. I had a friend fish with me recently, and he sold his Cannons shortly after and ordered Penns. Just one person's opinion!!! Good fishing. Mike