diff --git a/Source/PeleLMDerive.H b/Source/PeleLMDerive.H
index 4d0a5581..fa1e2793 100644
--- a/Source/PeleLMDerive.H
+++ b/Source/PeleLMDerive.H
@@ -102,7 +102,7 @@ protected:
    * \param interp
    */
   PeleLMDeriveRec(
-    const std::string& name,
+    std::string name,
     amrex::IndexType result_type,
     int nvar_derive,
     PeleLMDeriveFunc der_func,
@@ -121,7 +121,7 @@ protected:
    * \param interp
    */
   PeleLMDeriveRec(
-    const std::string& name,
+    std::string name,
     amrex::IndexType result_type,
     int nvar_derive,
     amrex::Vector<std::string>& var_names,
@@ -140,7 +140,7 @@ protected:
    * \param interp
    */
   PeleLMDeriveRec(
-    const std::string& name,
+    std::string name,
     amrex::IndexType result_type,
     int nvar_derive,
     DeriveBoxMap box_map,
@@ -158,7 +158,7 @@ protected:
    * \param interp
    */
   PeleLMDeriveRec(
-    const std::string& name,
+    std::string name,
     amrex::IndexType result_type,
     int nvar_derive,
     amrex::Vector<std::string>& var_names,
diff --git a/Source/PeleLMDerive.cpp b/Source/PeleLMDerive.cpp
index fca7e606..696ebe05 100644
--- a/Source/PeleLMDerive.cpp
+++ b/Source/PeleLMDerive.cpp
@@ -1,15 +1,16 @@
 #include <PeleLMDerive.H>
+#include <utility>
 
 using namespace amrex;
 
 PeleLMDeriveRec::PeleLMDeriveRec(
-  const std::string& a_name,
+  std::string a_name,
   IndexType result_type,
   int nvar_derive,
   PeleLMDeriveFunc der_func,
   DeriveBoxMap box_map,
   Interpolater* a_interp)
-  : derive_name(a_name),
+  : derive_name(std::move(a_name)),
     variable_names(),
     der_type(result_type),
     n_derive(nvar_derive),
@@ -20,14 +21,14 @@ PeleLMDeriveRec::PeleLMDeriveRec(
 }
 
 PeleLMDeriveRec::PeleLMDeriveRec(
-  const std::string& a_name,
+  std::string a_name,
   IndexType result_type,
   int nvar_derive,
   Vector<std::string>& var_names,
   PeleLMDeriveFunc der_func,
   DeriveBoxMap box_map,
   Interpolater* a_interp)
-  : derive_name(a_name),
+  : derive_name(std::move(a_name)),
     variable_names(var_names),
     der_type(result_type),
     n_derive(nvar_derive),
@@ -38,33 +39,33 @@ PeleLMDeriveRec::PeleLMDeriveRec(
 }
 
 PeleLMDeriveRec::PeleLMDeriveRec(
-  const std::string& a_name,
+  std::string a_name,
   IndexType result_type,
   int nvar_derive,
   DeriveBoxMap box_map,
   Interpolater* a_interp)
-  : derive_name(a_name),
+  : derive_name(std::move(a_name)),
     variable_names(),
     der_type(result_type),
     n_derive(nvar_derive),
-    func(nullptr),
+
     mapper(a_interp),
     bx_map(box_map)
 {
 }
 
 PeleLMDeriveRec::PeleLMDeriveRec(
-  const std::string& a_name,
+  std::string a_name,
   IndexType result_type,
   int nvar_derive,
   Vector<std::string>& var_names,
   DeriveBoxMap box_map,
   Interpolater* a_interp)
-  : derive_name(a_name),
+  : derive_name(std::move(a_name)),
     variable_names(var_names),
     der_type(result_type),
     n_derive(nvar_derive),
-    func(nullptr),
+
     mapper(a_interp),
     bx_map(box_map)
 {
@@ -73,8 +74,8 @@ PeleLMDeriveRec::PeleLMDeriveRec(
 PeleLMDeriveRec::~PeleLMDeriveRec()
 {
   func = nullptr;
-  mapper = 0;
-  bx_map = 0;
+  mapper = nullptr;
+  bx_map = nullptr;
 }
 
 const std::string&
@@ -200,17 +201,15 @@ PeleLMDeriveList::dlist()
 bool
 PeleLMDeriveList::canDerive(const std::string& name) const
 {
-  for (std::list<PeleLMDeriveRec>::const_iterator li = lst.begin(),
-                                                  End = lst.end();
-       li != End; ++li) {
+  for (const auto& li : lst) {
     // Can be either a component name ...
-    for (int i = 0; i < li->numDerive(); i++) {
-      if (li->variableName(i) == name) {
+    for (int i = 0; i < li.numDerive(); i++) {
+      if (li.variableName(i) == name) {
         return true;
       }
     }
     // ... or a derive name
-    if (li->derive_name == name) {
+    if (li.derive_name == name) {
       return true;
     }
   }
@@ -220,19 +219,17 @@ PeleLMDeriveList::canDerive(const std::string& name) const
 const PeleLMDeriveRec*
 PeleLMDeriveList::get(const std::string& name) const
 {
-  for (std::list<PeleLMDeriveRec>::const_iterator li = lst.begin(),
-                                                  End = lst.end();
-       li != End; ++li) {
+  for (const auto& li : lst) {
     // Can be either a component name ...
-    for (int i = 0; i < li->numDerive(); i++) {
-      if (li->variableName(i) == name) {
-        return &(*li);
+    for (int i = 0; i < li.numDerive(); i++) {
+      if (li.variableName(i) == name) {
+        return &li;
       }
     }
     // ... or a derive name
-    if (li->derive_name == name) {
-      return &(*li);
+    if (li.derive_name == name) {
+      return &li;
     }
   }
-  return 0;
+  return nullptr;
 }
diff --git a/Source/PeleLMDiagnostics.cpp b/Source/PeleLMDiagnostics.cpp
index c3cf424a..ea6eb035 100644
--- a/Source/PeleLMDiagnostics.cpp
+++ b/Source/PeleLMDiagnostics.cpp
@@ -52,9 +52,9 @@ void
 PeleLM::updateDiagnostics()
 {
   // Might need to update some internal data as the grid changes
-  for (int n = 0; n < m_diagnostics.size(); ++n) {
-    if (m_diagnostics[n]->needUpdate()) {
-      m_diagnostics[n]->prepare(
+  for (const auto& m_diagnostic : m_diagnostics) {
+    if (m_diagnostic->needUpdate()) {
+      m_diagnostic->prepare(
         finestLevel() + 1, Geom(0, finestLevel()), boxArray(0, finestLevel()),
         dmap, m_diagVars);
     }
@@ -87,15 +87,12 @@ PeleLM::doDiagnostics()
   }
 
   Vector<std::string> stateNames;
-  for (std::list<std::tuple<int, std::string>>::const_iterator
-         li = stateComponents.begin(),
-         End = stateComponents.end();
-       li != End; ++li) {
-    stateNames.push_back(get<1>(*li));
+  for (const auto& stateComponent : stateComponents) {
+    stateNames.push_back(get<1>(stateComponent));
   }
-  for (int n = 0; n < m_diagnostics.size(); ++n) {
-    if (m_diagnostics[n]->doDiag(m_cur_time, m_nstep)) {
-      m_diagnostics[n]->processDiag(
+  for (const auto& m_diagnostic : m_diagnostics) {
+    if (m_diagnostic->doDiag(m_cur_time, m_nstep)) {
+      m_diagnostic->processDiag(
         m_nstep, m_cur_time, GetVecOfConstPtrs(diagMFVec), m_diagVars);
     }
   }
diff --git a/Source/PeleLMEvolve.cpp b/Source/PeleLMEvolve.cpp
index 58ce411d..f46e8cb7 100644
--- a/Source/PeleLMEvolve.cpp
+++ b/Source/PeleLMEvolve.cpp
@@ -240,7 +240,7 @@ PeleLM::checkMessage(const std::string& a_action)
     int action_flag = 0;
     if (ParallelDescriptor::IOProcessor()) {
       FILE* fp;
-      if ((fp = fopen(action_file.c_str(), "r")) != 0) {
+      if ((fp = fopen(action_file.c_str(), "r")) != nullptr) {
         remove(action_file.c_str());
         action_flag = 1;
         fclose(fp);
diff --git a/Source/PeleLMPlot.cpp b/Source/PeleLMPlot.cpp
index c8910e70..6d8ed8db 100644
--- a/Source/PeleLMPlot.cpp
+++ b/Source/PeleLMPlot.cpp
@@ -477,8 +477,8 @@ PeleLM::WriteHeader(const std::string& name, bool is_checkpoint) const
 
     // Ambient pressure and typvals
     HeaderFile << m_pNew << "\n";
-    for (int n = 0; n < typical_values.size(); n++) {
-      HeaderFile << typical_values[n] << "\n";
+    for (double typical_value : typical_values) {
+      HeaderFile << typical_value << "\n";
     }
   }
 }
@@ -663,8 +663,8 @@ PeleLM::ReadCheckPointFile()
   is >> m_pNew;
   GotoNextLine(is);
   m_pOld = m_pNew;
-  for (int n = 0; n < typical_values.size(); n++) {
-    is >> typical_values[n];
+  for (double& typical_value : typical_values) {
+    is >> typical_value;
     GotoNextLine(is);
   }
 
diff --git a/Source/PeleLMSetup.cpp b/Source/PeleLMSetup.cpp
index 114e45c9..91bc8849 100644
--- a/Source/PeleLMSetup.cpp
+++ b/Source/PeleLMSetup.cpp
@@ -1137,8 +1137,8 @@ PeleLM::taggingSetup()
   ppamr.queryarr(
     "refinement_indicators", refinement_indicators, 0,
     ppamr.countval("refinement_indicators"));
-  for (int n = 0; n < refinement_indicators.size(); ++n) {
-    std::string ref_prefix = amr_prefix + "." + refinement_indicators[n];
+  for (const auto& refinement_indicator : refinement_indicators) {
+    std::string ref_prefix = amr_prefix + "." + refinement_indicator;
     ParmParse ppr(ref_prefix);
 
     // Tag a given box
@@ -1211,16 +1211,15 @@ PeleLM::taggingSetup()
       errTags.push_back(AMRErrorTag(info));
       itexists = true;
     } else {
-      Abort(
-        std::string(
-          "Unrecognized refinement indicator for " + refinement_indicators[n])
-          .c_str());
+      Abort(std::string(
+              "Unrecognized refinement indicator for " + refinement_indicator)
+              .c_str());
     }
 
     if (!itexists) {
       amrex::Error(
         "PeleLM::taggingSetup(): unknown variable field for criteria " +
-        refinement_indicators[n]);
+        refinement_indicator);
     }
   }
 }
diff --git a/Source/PeleLMTagging.cpp b/Source/PeleLMTagging.cpp
index d0bc9052..236aba54 100644
--- a/Source/PeleLMTagging.cpp
+++ b/Source/PeleLMTagging.cpp
@@ -22,13 +22,12 @@ PeleLM::ErrorEst(int lev, TagBoxArray& tags, Real time, int /*ng*/)
   }
 #endif
 
-  for (int n = 0; n < errTags.size(); ++n) {
+  for (const auto& errTag : errTags) {
     std::unique_ptr<MultiFab> mf;
-    if (errTags[n].Field() != std::string()) {
-      mf = deriveComp(errTags[n].Field(), time, lev, errTags[n].NGrow());
+    if (errTag.Field() != std::string()) {
+      mf = deriveComp(errTag.Field(), time, lev, errTag.NGrow());
     }
-    errTags[n](
-      tags, mf.get(), TagBox::CLEAR, TagBox::SET, time, lev, geom[lev]);
+    errTag(tags, mf.get(), TagBox::CLEAR, TagBox::SET, time, lev, geom[lev]);
   }
 
 #ifdef AMREX_USE_EB
diff --git a/Source/PeleLMUtils.cpp b/Source/PeleLMUtils.cpp
index 763a6891..1a672a52 100644
--- a/Source/PeleLMUtils.cpp
+++ b/Source/PeleLMUtils.cpp
@@ -1096,11 +1096,8 @@ bool
 PeleLM::isStateVariable(std::string_view a_name)
 {
   // Check state
-  for (std::list<std::tuple<int, std::string>>::const_iterator
-         li = stateComponents.begin(),
-         End = stateComponents.end();
-       li != End; ++li) {
-    if (std::get<1>(*li) == a_name) {
+  for (const auto& stateComponent : stateComponents) {
+    if (std::get<1>(stateComponent) == a_name) {
       return true;
     }
   }
@@ -1111,11 +1108,8 @@ bool
 PeleLM::isReactVariable(std::string_view a_name)
 {
   // Check reaction state
-  for (std::list<std::tuple<int, std::string>>::const_iterator
-         li = reactComponents.begin(),
-         End = reactComponents.end();
-       li != End; ++li) {
-    if (std::get<1>(*li) == a_name) {
+  for (const auto& reactComponent : reactComponents) {
+    if (std::get<1>(reactComponent) == a_name) {
       return true;
     }
   }
@@ -1131,12 +1125,9 @@ PeleLM::stateVariableIndex(std::string_view a_name)
       "PeleLM::stateVariableIndex(): unknown State variable: " +
       static_cast<std::string>(a_name));
   }
-  for (std::list<std::tuple<int, std::string>>::const_iterator
-         li = stateComponents.begin(),
-         End = stateComponents.end();
-       li != End; ++li) {
-    if (std::get<1>(*li) == a_name) {
-      idx = std::get<0>(*li);
+  for (const auto& stateComponent : stateComponents) {
+    if (std::get<1>(stateComponent) == a_name) {
+      idx = std::get<0>(stateComponent);
     }
   }
   return idx;
@@ -1151,12 +1142,9 @@ PeleLM::reactVariableIndex(std::string_view a_name)
       "PeleLM::reactVariableIndex(): unknown Reaction variable: " +
       static_cast<std::string>(a_name));
   }
-  for (std::list<std::tuple<int, std::string>>::const_iterator
-         li = reactComponents.begin(),
-         End = reactComponents.end();
-       li != End; ++li) {
-    if (std::get<1>(*li) == a_name) {
-      idx = std::get<0>(*li);
+  for (const auto& reactComponent : reactComponents) {
+    if (std::get<1>(reactComponent) == a_name) {
+      idx = std::get<0>(reactComponent);
     }
   }
   return idx;
@@ -1790,11 +1778,11 @@ PeleLM::parseComposition(
 
   // Ensure that it sums to 1.0:
   Real sum = 0.0;
-  for (int k = 0; k < NUM_SPECIES; k++) {
-    sum += compoIn[k];
+  for (double k : compoIn) {
+    sum += k;
   }
-  for (int k = 0; k < NUM_SPECIES; k++) {
-    compoIn[k] /= sum;
+  for (double& k : compoIn) {
+    k /= sum;
   }
 
   // Fill the massFrac array, convert from mole fraction if necessary
diff --git a/Source/PeleLM_K.H b/Source/PeleLM_K.H
index 571cb879..0dab5d95 100644
--- a/Source/PeleLM_K.H
+++ b/Source/PeleLM_K.H
@@ -308,8 +308,8 @@ compute_divu(
   amrex::Real hi[NUM_SPECIES] = {0.0};
   eos.T2Hi(T(i, j, k), hi);
   cpmix *= 1.0e-4_rt; // CGS -> MKS conversion
-  for (int n = 0; n < NUM_SPECIES; n++) {
-    hi[n] *= 1.0e-4_rt; // CGS -> MKS conversion
+  for (double& n : hi) {
+    n *= 1.0e-4_rt; // CGS -> MKS conversion
   }
 
   amrex::Real denominv = 1.0_rt / (rho * cpmix * T(i, j, k));