Clean water is a vital necessity in everyday life, however, sometimes there are obstacles in the supply of water to households due to the murky condition of dug well water. One of the chemicals that has the potential to be used to reduce turbidity is alum. So research is needed which aims to test the effectiveness of alum to purify dug well water using a simple filtering mechanism. This experimental study used the same well water sample and then separated it into three groups: filtering mechanism I used alum, mechanism II used quicklime and the third was a control. After going through the filtering process, an examination of the turbidity level of the three water samples was carried out. Furthermore, a comparative analysis was carried out between the three using the Anova test. The results of the analysis showed that the highest level of turbidity was the control, followed by filtering mechanism II using quicklime and the lowest was mechanical filtering I using alum. The mean turbidity level scores of the three respectively were 510.00, 317.67 and 201.00. While the p values for each comparison were: control vs quicklime = 0.000, control vs alum = 0.000, while quicklime vs alum = 0.003. Based on the results of the study it can be concluded that alum is a good chemical for purifying water with a simple filtering mechanism.