diff --git a/src/MC/fix_charge_regulation.cpp b/src/MC/fix_charge_regulation.cpp
index 0aa3def153..797d7fb5b0 100644
--- a/src/MC/fix_charge_regulation.cpp
+++ b/src/MC/fix_charge_regulation.cpp
@@ -130,7 +130,7 @@ FixChargeRegulation::~FixChargeRegulation() {
 
   delete random_equal;
   delete random_unequal;
-  delete idftemp;
+  delete[] idftemp;
 
   if (group) {
     int igroupall = group->find("all");