Lure size is important. The rule of thumb is use smaller lures to catch smaller fish and larger lures to catch larger fish. Keep in mind plain spinners present a smaller profile than dressed spinners, so they will appear smaller to the fish. This makes them perfect for panfish and small stream trout.
Fishing with dressed spinners can produce larger fish, but, when stream trout fishing, you will probably catch more fish using plain spinners.
Mepps single hook Aglias can be used virtually anywhere single hook lures are required. They are perfect for Alaska.
Mepps Size 0 - are perfect for panfish (bluegills or sunfish) and small stream trout. They are very light, however, and require a nimble rod, equipped with a light action reel spooled with light line; nothing heavier than six-pound-test. Two-pound-test to four-pound-test is better.
Mepps Size 1 & 2 - are perfect for larger stream trout and large bluegills, sunfish and crappies. Size #2 Aglias are also excellent for smallmouth bass and walleye. These sizes are ideal for teaching youngsters the basics of spinner fishing, as they are heavy enough to cast well with light tackle, yet they are small enough to catch a wide variety of fish.
Mepps Size 3 - are preferred by largemouth bas fisherman.
Mepps Size 4 - are ideal for large rainbow trout and steelhead, as well as coho (silver) and chinook (king) salmon.