diff --git a/src/gpu/GridGenerator/grid/GridBuilder/GridBuilder.h b/src/gpu/GridGenerator/grid/GridBuilder/GridBuilder.h
index c9aa7678b9d4391a47707880a2fcb9eb90547864..d4893c3c23a788bfd2d1b9199988590b9bbd93d1 100644
--- a/src/gpu/GridGenerator/grid/GridBuilder/GridBuilder.h
+++ b/src/gpu/GridGenerator/grid/GridBuilder/GridBuilder.h
@@ -147,9 +147,9 @@ public:
 
     virtual void findFluidNodes(bool splitDomain) = 0;
 
-    virtual void addFluidNodeIndicesMacroVars(std::vector<uint> fluidNodeIndicesMacroVars, uint level)           = 0;
-    virtual void addFluidNodeIndicesApplyBodyForce(std::vector<uint> fluidNodeIndicesApplyBodyForce, uint level) = 0;
-    virtual void addFluidNodeIndicesAllFeatures(std::vector<uint> fluidNodeIndicesAllFeatures, uint level)       = 0;
+    virtual void addFluidNodeIndicesMacroVars(const std::vector<uint>& fluidNodeIndicesMacroVars, uint level)           = 0;
+    virtual void addFluidNodeIndicesApplyBodyForce(const std::vector<uint>& fluidNodeIndicesApplyBodyForce, uint level) = 0;
+    virtual void addFluidNodeIndicesAllFeatures(const std::vector<uint>& fluidNodeIndicesAllFeatures, uint level)       = 0;
     virtual void sortFluidNodeIndicesMacroVars(uint level) = 0;
     virtual void sortFluidNodeIndicesApplyBodyForce(uint level) = 0;
     virtual void sortFluidNodeIndicesAllFeatures(uint level) = 0;
diff --git a/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.cpp b/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.cpp
index 267f03c5aefa809f68af6d9750cf4afbf3cfe3e2..a797fdf011d4441344da82249090448b511a5491 100644
--- a/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.cpp
+++ b/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.cpp
@@ -798,17 +798,17 @@ void LevelGridBuilder::findFluidNodes(bool splitDomain)
 }
 
 
-void LevelGridBuilder::addFluidNodeIndicesMacroVars(std::vector<uint> fluidNodeIndicesMacroVars, uint level) 
+void LevelGridBuilder::addFluidNodeIndicesMacroVars(const std::vector<uint>& fluidNodeIndicesMacroVars, uint level) 
 {
     grids[level]->addFluidNodeIndicesMacroVars(fluidNodeIndicesMacroVars);
 }
 
-void LevelGridBuilder::addFluidNodeIndicesApplyBodyForce(std::vector<uint> fluidNodeIndicesApplyBodyForce, uint level)
+void LevelGridBuilder::addFluidNodeIndicesApplyBodyForce(const std::vector<uint>& fluidNodeIndicesApplyBodyForce, uint level)
 {
     grids[level]->addFluidNodeIndicesApplyBodyForce(fluidNodeIndicesApplyBodyForce);
 }
 
-void LevelGridBuilder::addFluidNodeIndicesAllFeatures(std::vector<uint> fluidNodeIndicesAllFeatures, uint level)
+void LevelGridBuilder::addFluidNodeIndicesAllFeatures(const std::vector<uint>& fluidNodeIndicesAllFeatures, uint level)
 {
     grids[level]->addFluidNodeIndicesAllFeatures(fluidNodeIndicesAllFeatures);
 }
diff --git a/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.h b/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.h
index cc6f31800c2e55ca604ff2f223475ba54d3afd56..cf422c8bba0d0171c0c2a4868076297c39f0579d 100644
--- a/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.h
+++ b/src/gpu/GridGenerator/grid/GridBuilder/LevelGridBuilder.h
@@ -211,9 +211,9 @@ public:
     // needed for CUDA Streams MultiGPU (Communication Hiding)
     void findFluidNodes(bool splitDomain) override;
 
-    void addFluidNodeIndicesMacroVars(std::vector<uint> fluidNodeIndicesMacroVars, uint level) override;
-    void addFluidNodeIndicesApplyBodyForce(std::vector<uint> fluidNodeIndicesApplyBodyForce, uint level) override;
-    void addFluidNodeIndicesAllFeatures(std::vector<uint> fluidNodeIndicesAllFeatures, uint level) override;
+    void addFluidNodeIndicesMacroVars(const std::vector<uint>& fluidNodeIndicesMacroVars, uint level) override;
+    void addFluidNodeIndicesApplyBodyForce(const std::vector<uint>& fluidNodeIndicesApplyBodyForce, uint level) override;
+    void addFluidNodeIndicesAllFeatures(const std::vector<uint>& fluidNodeIndicesAllFeatures, uint level) override;
     
     void sortFluidNodeIndicesMacroVars(uint level) override;
     void sortFluidNodeIndicesApplyBodyForce(uint level) override;