The experimental facility was located in a glasshouse on the University of Washington campus (Seattle, WA). The facility consisted of six integrated systems and two control systems. Three experimental treatments and one control treatment were used for each of three 28-day trials. The experimental treatments had different initial biomasses of fish. Treatments for trial 1 (151, 377, and 902 g fish/system) and trials 2 and 3 (377, 902, and 1804 g fish/system) were conducted in duplicate. Control treatments contained no fish and were duplicated in all trials.