| Group | Alum (mg/L) | pH   | Color (PtCo) | Turbidity (NTU) |
| ----- | ----------- | ---- | ------------ | --------------- |
| 1     | 24          | 6.58 | 68           | 8.79            |
| 2     | 48          | 6.62 | 45           | 4.06            |
| 3     | 72          | 6.73 | 24           | 2.6             |
| 4     | 120         | 6.53 | 15           | 1.55            |
| 5     | 168         | 6.51 | 33           | 3.68            |
| 6     | 240         | 6.36 | 23           | 3.85            |

Optimum alum = 122 mg/L