A study at the University of Newcastle-upon-Tyne (UK) found that Moringa seeds not only purify water but also soften it.
The results of this study are found in:
Suleyman A. Muyibi and Lilian M. Evison, "Moringa oleifera Seeds for Softening Hardwater," Water Research, Vol. 29, No. 4, 1995, pp.1099-1105.