Try small minnows or tiny tubes onder a small float, minnows are probably better. You just have to figure out what depth they are suspending at to really yet into them, but that shouldn't be to hard if its 4 feet deep, now should it?
If there is a stream flowing in, fishing there is probably a good idea, just remember that fish always face the current. I would probably fish just above the weeds if they dominate the lake.
Good Luck and Tight Lines!
-Wes