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Introduction
In order to test the calcium carbonate hypothesis developed by the Fall 2009 team, the Spring 2010 team ran a second experiment to compare the performance of the reactors using distilled water versus tap water. There should be no carbonates present in the distilled water, so if the formation of calcium carbonate precipitate inhibiting dissolution is what is limiting the reactor's performance, the use of distilled water should produce better results. The two runs in this experiment were identical except for the water type so that that variable could be isolated.
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The similarity in performance between the A2 apparatus run with tap water and the A2 apparatus run with distilled water indicates that calcium carbonate precipitate may not be the main issue. Failure with distilled water suggests that there must be another issue. See the hypotheses page for further information.