Using a protein rest may help (or may not, depending). Shamelessly copied from "How to Brew" by John Palmer. "The typical Protein Rest at 120 - 130°F is used to break up proteins which might otherwise cause chill haze and can improve the head retention. This rest should only be used when using moderately-modified malts, or when using fully modified malts with a large proportion (>25%) of unmalted grain, e.g. flaked barley, wheat, rye, or oatmeal. Using this rest in a mash consisting mainly of fully modified malts would break up the proteins responsible for body and head retention and result in a thin, watery beer. The standard time for a protein rest is 20 - 30 minutes". I have only used the rest on wheat beers, and get great foam from them, but more retention with German malts. Based on this, I'll try skipping the protein rest on my next American wheat and see how it compares.