10. How to set your indicator to the correct depth. (10 of 21)

The placement of an indicator on your leader is critical. A good rule of thumb, especially in faster water is to set your indicator about one and a half to two times the water depth above your first fly or weight. This is because in fast water, the indicator is on the surface where the water is faster, but trout are closer to the bottom where the current is slower. So your fly drifts at an angle to the indicator, through most of the drift, the faster the water, the more you want to favor a longer depth.
And conversely, in really slow water, you might need to set your indicator at just about the water depth, especially with heavier flies. Once you set your indicator, initially, it's likely you'll have to move it. You can gauge this by looking at a number of things. First, you should be occasionally snagging by, or you should see the indicator ticking along the bottom.
It looks like the indicator is stuttering a bit. If this is not happening every half dozen drifts, you know, you're not getting deep enough and need to move your indicator up the leader, 3 to 6 inches closer to the rod tip. You should be be getting snagged. And if you're not losing flies, you're probably not fishing deep enough. On the other hand, if you're getting hung up too frequently, every two or three casts, it's time to raise the indicator, a few inches to move your flies a bit off the bottom.
Trout don't eat right on the bottom, they feed just above the bottom. Beside your indicator height, you should also adjust the weight of your flies. It's really a combination of indicator placement and weight. And you can adjust based on either or both. Most anglers and guides agree that if you can get the right weight by using weighted flies, you're better off because putting weight on the leader makes casting tougher and tangles nastier.
This is why a smart angler will have flies with different weights. Some unweighted, some with brass beads and some with tungsten beads, which are heavier than brass. And of course, to further fine-tune your weight, you can add weight on the leader to add sink rate to your flies. We'll deal with added weight on the leader short.