diff --git a/idaes/core/base/property_set.py b/idaes/core/base/property_set.py
index d895c5a93b..e0e94f70aa 100644
--- a/idaes/core/base/property_set.py
+++ b/idaes/core/base/property_set.py
@@ -969,11 +969,6 @@ class StandardPropertySet(PropertySetBase):
         doc="Reaction Rate",
         units=pyunits.dimensionless,
     )
-    saturation_index = PropertyMetadata(
-        name="saturation_index",
-        doc="Saturation Index = log(IAP/Ksp)",
-        units=pyunits.dimensionless,
-    )
 
 
 class ElectrolytePropertySet(StandardPropertySet):
@@ -1032,3 +1027,8 @@ class ElectrolytePropertySet(StandardPropertySet):
         doc="Log of equilibrium coefficient",
         units=pyunits.dimensionless,
     )
+    saturation_index = PropertyMetadata(
+        name="saturation_index",
+        doc="Saturation Index = log(IAP/Ksp)",
+        units=pyunits.dimensionless,
+    )