A total of 27 cards from 19 hobbyists was returned and survived shipping and handling. Each participant estimated tank volume and total current, including powerheads and pumps returning water from the sump, and listed the pumps used. The average loss for the participants was 35.5 percent 9.8 percent. The highest dissolution was 45.4 percent, while the lowest was 12.4 percent. This means the most turbulent tanks exceeded the Bonaire surge zone, while the majority of tanks more closely resembled back reef or lagoonal energies in their water motion.
Few writers offer recommendations on what constitutes adequate water motion in the reef tank.
Those daring souls who offer a suggestion generally express the recommendation based on tank volume turnover. The assumption has been that higher turnover rates translate into higher tank turbulent flow. This turned out to be untrue for the hobbyist tanks studied. Figure 3 shows the results of the first wave of testing. Regression suggests a negative relationship in which dissolution goes down as turnover goes up.