4.  Advantages.

1. Wider application, better water adaptation. 
2. Quickly shape big alum bubble, and with good precipitation. 
3. Better adaptation to PH value(5-9), and little declining range of PH value and alkalinity of water after treatment. 
4. Keeping stable precipitation effect at lower water temperature. 
5. Higher alkalization than other aluminium salt and iron salt, and little erosion to equipments.