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The team used the same procedure described on materials and methods. The lime was added as dry powder. For the up-flow velocity of 3.6 mm/sec, it was calculated that 20g of lime were required for the effluent to be saturated for 12 hours.
Results
The following graph Figure 1. shows effluent pH over time. A1 The green line represents the small reactor and A2 represents the larger one2.5cm diameter tube settler, and the 5cm diameter tube settler is represented by yellow and orange lines. We can see that none of the runs were anywhere close to reaching the goal of twelve hours with a saturated effluent. Both the tap water and distilled water runs with the large apparatus 5cm diameter tube settler failed within an hour and a half, while the run with the small apparatus 2.5 cm diameter tube settler never produced any saturated effluent. There is certainly no performance improvement running the reactor with distilled water. 
The following graph
Figure 1. Effluent pH vs time in hours. Comparison of performance between tap water and distilled water.
Figure 2. shows the fraction of saturated hydroxide concentration versus the fraction of time the run is theoretically calculated to last. This is simply a clearer way to display the reactor's performance over the course of the experiment relative to our goal, which would be to have a straight line at an OH fraction of one. In this case, the chart Figure 2. illustrates what are likely measurement errors: a hydroxide concentration nearly double the saturation value in one run and a failure to reach saturation in what should be an identical trial.
Figure 2. Fraction of saturated hydroxide vs Fraction of time
Discussion
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.