S&DSI — Stiff & Davis Stability Index
High-TDS companion to LSI. Use for RO reject, seawater and brackish water above roughly 10,000 mg/L TDS, where LSI loses accuracy.
Ionic strength I
0.375mol/L
K(I,T)
2.29
Saturation pH (pHs)
6.69
S&DSI · Scale-forming
+1.11
Tendency to scale on RO membranes and heat surfaces. Antiscalant advised.