| Factors | Low-level | High-level |
A | pH | 5.5 | 7.5 |
B | Ca/P | 1.53 | 1.67 |
C | mCa (g) | 0.666 | 1 |
D | t (hours) | 3 | 5 |
E | T (˚C) | 60 | 90 |