Your question really is a very basic one.
However, that does not mean the answer is simple. What you have asked breaks down to three questions that are at the core of fly fishing.
What were the brookies taking, what fly match the hatch, and how do I present the fly?
Answering those 3 questions form the basis of a fly fishing strategy. The lack of a coherent strategy results in playing a fly box lottery in which you try different flies hoping to hit the right one.
I suggest you read this thread on matching the hatch.
Help with Matching Hatches
Then I suggest you read my FAQ on fishing the dry fly
that I wrote for the Flyfish@ mailing list. follow up with my other FAQs
Henry's faqs menu
I also need to ask whether you are familiar with rise forms.
If you look very carefully, you can tell how the fish took the aquatic insect, and where the insect was in the water column.
Here is an illustration from Field and Stream that shows:
1. A sipping rise to an insect trapped in or on the film, fine rings in the water = emerger, stillborn emerger, spinner, some small midges.
2. The slurping rise leaves a bubble, the fish's mouth breaks the surface to take a fully emerged insect = mayfly duns and other insects that have fully hatched.
3. The splashy rise, the fish slashes at the fly = typically a rise to caddis that can fly off immediately or a large terrestrial on the water like a grasshopper. The fish want the insect not to escape OR wants to beat another fish to the food.
4. The boil or head and shoulder rise. The water bulges but the fish's mouth does not break the water. The fish's shoulder or dorsal fin may break the water as the fish heads back down = The fish is feeding below the surface chasing nymphs or pupa that are rising in the water column to hatch. They are intercepting the food on the way to the surface and overshoot and break the surface or cause a bulge of water.
Now apply that to what you have written:
Originally Posted by pikefisher69
I went up to the East Branch Eau Claire River in Wisconsin…. I was fishing on it for 2 hours, before I lost my mind because of leader and tipper tangle ups, and I didn't catch anything except for 3 shiners. I saw a large amount of rises and some fish jumping and rising, which I knew were brookies because of their brownish orange bellies, and I couldn't tell what they were jumping and rising for. There appeared to be nothing but the occasional caddis fly on the water and that was it. I casted out a few different flies from a purple haze to an adams to even a pass lake (I could really only use dry flies since there was so much algae or weeds underwater). Some brook trout jumped either right next to my fly or at it and I got no hook ups on them.
Has this ever happened to you? If so, what did you do to solve it?
So what were the fish feeding on? From the patterns you mentioned, you never said you tried a caddis which is the one insect that you saw on teh water. Also the splashy rises suggest to me that the fish were feeding on caddis.
So I would start with a tan or grey X-caddis and depending on the response of the fish, I might go down a size. Why smaller? Because fly fishers tend to overestimate the actual size of a caddis fly especially when they are flying.
My backup fly would be an earlier stage of a caddis emerger with an iris caddis pattern.
If that did not work, you go to an even earlier stage and try wither a soft hackle OR a caddis pupa pattern using the Leisering lift.
BTW, where do you live pikefisher?