I just wanted to add an illustration to my comments about carrying capacity. Many people think that carrying capacity is a constant. Say this number is 500 pounds per acre. Some people think that if you have 4 species, each species would have 125 pounds. If you add a 5th species, each species would only have 100 pounds.
You can see that this isn't true by thinking of LMB. Using our illustration above, if you want to raise LMB, the addition of bluegills is just a waste. You could have 500 pounds of LMB and forget the forage. We use forage species because they use parts of the environment that LMB don't. That is true of every species we add, they are all a bit more specialized in using the environment than other species. The total amount of biomass increases. However, because of the increased competition, individuals don't grow as fast or get as big as they would without this extreme competition.
All of this is to say that in general, your idea of another forage species is valid. The point that Dave Willis was making is that white suckers are very good at exploiting this type of environment and may dominate this lake.
Dave recommended that I add white suckers to my 4 acre lake because I have such a preponderance of large predators. If you should add white suckers, make sure you have enough predators to control their numbers. It can be done.
