diff --git a/bench/fgcs/dolo_fgcs.pqi b/bench/fgcs/dolo_fgcs.pqi
index 39e8553a4..84c55875f 100644
--- a/bench/fgcs/dolo_fgcs.pqi
+++ b/bench/fgcs/dolo_fgcs.pqi
@@ -4,6 +4,8 @@ SOLUTION 1
     temperature	25
     pH	7
     pe	4
+    Mg 1e-12
+    Cl 2e-12
 PURE 1
     Calcite 0.0 1
 END