diff --git a/DEMSystems/sphereDEMSystem/sphereDEMSystem.cpp b/DEMSystems/sphereDEMSystem/sphereDEMSystem.cpp
index 8416e505..37f7529f 100644
--- a/DEMSystems/sphereDEMSystem/sphereDEMSystem.cpp
+++ b/DEMSystems/sphereDEMSystem/sphereDEMSystem.cpp
@@ -25,8 +25,6 @@ bool pFlow::sphereDEMSystem::loop()
 
 	do 
 	{
-		Control().timers().start();
-
 		//
 		
 		if(! insertion_().insertParticles( 
@@ -55,9 +53,6 @@ bool pFlow::sphereDEMSystem::loop()
 		particles_->afterIteration();
 		
 		geometry_->afterIteration();
-		
-
-		Control().timers().end();
 
 	}while(Control()++);
 
@@ -80,9 +75,11 @@ pFlow::sphereDEMSystem::sphereDEMSystem(
 	REPORT(0)<< "\nCreating surface geometry for sphereDEMSystem . . . "<<endREPORT;
 	geometry_ = geometry::create(Control(), Property());
 
+
 	REPORT(0)<<"\nReading sphere particles . . ."<<endREPORT;
 	particles_ = makeUnique<sphereFluidParticles>(Control(), Property());
 
+
 	insertion_ = makeUnique<sphereInsertion>(
 		Control().caseSetup().path()+insertionFile__, 
 		particles_(), 
diff --git a/DEMSystems/sphereDEMSystem/sphereFluidParticles.cpp b/DEMSystems/sphereDEMSystem/sphereFluidParticles.cpp
index 386ac859..9b3a44b0 100644
--- a/DEMSystems/sphereDEMSystem/sphereFluidParticles.cpp
+++ b/DEMSystems/sphereDEMSystem/sphereFluidParticles.cpp
@@ -54,6 +54,13 @@ pFlow::sphereFluidParticles::sphereFluidParticles(
 		)
 {} 
 
+bool pFlow::sphereFluidParticles::beforeIteration()
+{
+	sphereParticles::beforeIteration();
+	zeroFluidForce_H();
+	zeroFluidTorque_H();
+	return true;
+}
 
 
 bool pFlow::sphereFluidParticles::iterate() 
diff --git a/DEMSystems/sphereDEMSystem/sphereFluidParticles.hpp b/DEMSystems/sphereDEMSystem/sphereFluidParticles.hpp
index 48b73f34..9890dac8 100644
--- a/DEMSystems/sphereDEMSystem/sphereFluidParticles.hpp
+++ b/DEMSystems/sphereDEMSystem/sphereFluidParticles.hpp
@@ -48,12 +48,24 @@ protected:
 	realx3PointField_HD& 	fluidTorque_;
 
 
+	void zeroFluidForce_H()
+	{
+		fluidForce_.fillHost(zero3);
+	}
+
+	void zeroFluidTorque_H()
+	{
+		fluidTorque_.fillHost(zero3);
+	}
+
 public:
 
 	/// construct from systemControl and property 
 	sphereFluidParticles(systemControl &control, const property& prop);
 	
-
+	/// before iteration step 
+	bool beforeIteration() override;
+	
 	/// iterate particles 
 	bool iterate() override;	
 
diff --git a/solvers/sphereGranFlow/sphereGranFlow.cpp b/solvers/sphereGranFlow/sphereGranFlow.cpp
index a4920b86..7b9785cf 100755
--- a/solvers/sphereGranFlow/sphereGranFlow.cpp
+++ b/solvers/sphereGranFlow/sphereGranFlow.cpp
@@ -65,7 +65,6 @@ if(!cmds.parse(argc, argv)) return 0;
 
 	do 
 	{
-		Control.timers().start();
 		
 		if(! sphInsertion.insertParticles( 
 			Control.time().currentTime(),
@@ -94,8 +93,6 @@ if(!cmds.parse(argc, argv)) return 0;
 		surfGeometry.afterIteration();
 		
 
-		Control.timers().end();
-
 	}while(Control++);
 
 	REPORT(0)<<"\nEnd of time loop.\n"<<endREPORT;
diff --git a/src/Particles/SphereParticles/sphereParticles/sphereParticles.cpp b/src/Particles/SphereParticles/sphereParticles/sphereParticles.cpp
index 6191a22e..f4908782 100644
--- a/src/Particles/SphereParticles/sphereParticles/sphereParticles.cpp
+++ b/src/Particles/SphereParticles/sphereParticles/sphereParticles.cpp
@@ -72,8 +72,11 @@ bool pFlow::sphereParticles::diameterMassInertiaPropId
 
 bool pFlow::sphereParticles::initializeParticles()
 {
-		
-	int32IndexContainer indices(0, shapeName_.size());
+	
+	int32IndexContainer indices(
+		0, 
+		static_cast<int32>(shapeName_.size()));
+	
 	return insertSphereParticles(shapeName_, indices);
 }
 
@@ -148,7 +151,7 @@ bool pFlow::sphereParticles::insertSphereParticles(
 	}
 
 	auto len = names.size();
-	
+		
 	realVector  diamVec(len, RESERVE());
 	realVector  massVec(len, RESERVE());
 	realVector  IVec(len, RESERVE());
@@ -160,6 +163,7 @@ bool pFlow::sphereParticles::insertSphereParticles(
 
 	ForAll(i, names )
 	{
+		
 		if (diameterMassInertiaPropId(names[i], d, m, I, pId))
 		{
 			diamVec.push_back(d);
@@ -297,7 +301,6 @@ pFlow::sphereParticles::sphereParticles(
 		fatalExit;
 	}
 
-	
 	if(rVelIntegration_->needSetInitialVals())
 	{
 		
@@ -320,6 +323,7 @@ pFlow::sphereParticles::sphereParticles(
 
 	}
 
+	
 	if(!initializeParticles())
 	{
 		fatalExit;
diff --git a/src/phasicFlow/Timer/Timer.cpp b/src/phasicFlow/Timer/Timer.cpp
index 9031104e..9a4546e4 100644
--- a/src/phasicFlow/Timer/Timer.cpp
+++ b/src/phasicFlow/Timer/Timer.cpp
@@ -77,18 +77,24 @@ bool pFlow::Timer::write(iOstream& os, bool subTree)const
 	
 	if(lvl==0)
 		os<<greenColor<<boldChar;
+	else if(master())
+		os<<yellowColor;
+
 
 	os<<name_;
 
-	if(timerActive())
-		if(master())
-			os<<" execution time (s): total ("<<
-				totalTime()<<"), av. ("<<
-				averageTime()<<").";
-		else
-			os<<" execution time (s): total ("<<
-				cyanText(totalTime())<<"), av. ("<<
-				cyanText(averageTime())<<").";
+	auto tt = accTimersTotal();
+	if(abs(tt)>smallValue)
+	{
+		os<<" execution time (s): total ("<<
+			tt<<")";
+
+		if(!master())
+		{
+			os<<", av. ("<<
+			averageTime()<<").";	
+		}
+	}		
 
 	os<<defaultColor;
 	os<<'\n';
diff --git a/src/phasicFlow/Timer/Timer.hpp b/src/phasicFlow/Timer/Timer.hpp
index bb6a6817..54e30317 100644
--- a/src/phasicFlow/Timer/Timer.hpp
+++ b/src/phasicFlow/Timer/Timer.hpp
@@ -109,31 +109,40 @@ public:
 		accTime_ += lastTime_;
 	}
 
+	inline
 	bool timerActive()const
 	{
 		return numIteration_!=0;
 	}
 
+	inline
 	real lastTime()const
 	{
 		return lastTime_;
 	}
 
+	inline
 	real totalTime()const
 	{
 		return accTime_;
 	}
 
+	inline
 	real averageTime()const
 	{
 
 		return accTime_/max(numIteration_, 1);
 	}
 
+	virtual
+	real accTimersTotal()const
+	{
+		return totalTime();
+	}
+
 	//// - IO operations
 
 	virtual bool write(iOstream& os, bool subTree)const;
-	
 
 	virtual bool read(iIstream& is)
 	{
diff --git a/src/phasicFlow/Timer/Timers.cpp b/src/phasicFlow/Timer/Timers.cpp
index 16db7b0c..b479ba5a 100644
--- a/src/phasicFlow/Timer/Timers.cpp
+++ b/src/phasicFlow/Timer/Timers.cpp
@@ -21,6 +21,27 @@ Licence:
 
 #include "Timers.hpp"
 
+pFlow::real pFlow::Timers::accTimersTotal()const
+{
+	// first this timer
+	real total = 0;
+	if(this->timerActive()) total += this->totalTime();
+
+	for(const auto tmr:timers_)
+	{
+		if(tmr -> master())
+		{
+			total += dynamic_cast<const Timers*>(tmr)->accTimersTotal();
+		}
+		else if(tmr->timerActive())
+		{
+			total += tmr->totalTime();
+		}
+	}
+
+	return total;
+}
+
 
 bool pFlow::Timers::write(iOstream& os, bool subTree)const
 {
diff --git a/src/phasicFlow/Timer/Timers.hpp b/src/phasicFlow/Timer/Timers.hpp
index 087b37ea..cd2630fb 100644
--- a/src/phasicFlow/Timer/Timers.hpp
+++ b/src/phasicFlow/Timer/Timers.hpp
@@ -18,8 +18,8 @@ Licence:
 
 -----------------------------------------------------------------------------*/
 
-#ifndef __Timers_hpp__ 
-#define __Timers_hpp__
+#ifndef __Timerss_hpp__ 
+#define __Timerss_hpp__
 
 
 #include "Timer.hpp"
@@ -30,11 +30,11 @@ namespace pFlow
 
 class Timers
 :
-	public Timer
+	public pFlow::Timer
 {
 protected:
 
-	List<Timer*> 	timers_;
+	List<pFlow::Timer*> 	timers_;
 
 	int32 			level_ = 0;
 
@@ -93,6 +93,8 @@ public:
 		return true;
 	}
 
+	real accTimersTotal()const override;
+
 	virtual bool write(iOstream& os, bool subTree = true)const;
 	
 
diff --git a/src/phasicFlow/containers/indexContainer/indexContainer.hpp b/src/phasicFlow/containers/indexContainer/indexContainer.hpp
index ddb3ccb8..14e88726 100644
--- a/src/phasicFlow/containers/indexContainer/indexContainer.hpp
+++ b/src/phasicFlow/containers/indexContainer/indexContainer.hpp
@@ -26,6 +26,7 @@ Licence:
 #include "KokkosUtilities.hpp"
 #include "ViewAlgorithms.hpp"
 
+
 namespace pFlow
 {
 
@@ -79,8 +80,8 @@ public:
 		size_(end-begin),
 		views_("indexContainer", size_)
 	{
-		pFlow::fillSequence(views_.d_view, 0, size_, min_);
-		copy(views_.h_view, views_.d_view);
+		pFlow::fillSequence(views_.h_view, 0, size_, min_);
+		copy(views_.d_view, views_.h_view);
 	}
 
 
diff --git a/src/phasicFlow/repository/Time/timeControl.cpp b/src/phasicFlow/repository/Time/timeControl.cpp
index 02e94359..d27aac1a 100644
--- a/src/phasicFlow/repository/Time/timeControl.cpp
+++ b/src/phasicFlow/repository/Time/timeControl.cpp
@@ -100,6 +100,19 @@ pFlow::timeControl::timeControl(
 	checkForOutputToFile();
 }
 
+bool pFlow::timeControl::finalTime()const
+{
+	if( currentTime_ >= endTime_ ) return true;
+	if( abs(currentTime_-endTime_) < 0.5*dt_ )return true;
+	return false;	
+}
+
+bool pFlow::timeControl::reachedStopAt()const
+{
+	if( currentTime_ >= stopAt_ ) return true;
+	if( abs(currentTime_-stopAt_) < 0.5*dt_ )return true;
+	return false;
+}
 
 void pFlow::timeControl::checkForOutputToFile()
 {
@@ -124,10 +137,13 @@ void pFlow::timeControl::checkForOutputToFile()
 		{
 			lastSaved_ = currentTime_;
 			save = true;
-		}	
+		}
+		
 	}
 
 	outputToFile_ = save;
+
+
 }
 
 bool pFlow::timeControl::timersReportTime()const
diff --git a/src/phasicFlow/repository/Time/timeControl.hpp b/src/phasicFlow/repository/Time/timeControl.hpp
index 2051f1ac..59d9fc21 100644
--- a/src/phasicFlow/repository/Time/timeControl.hpp
+++ b/src/phasicFlow/repository/Time/timeControl.hpp
@@ -152,18 +152,9 @@ public:
 		return currentIter_;
 	}
 
-	bool finalTime()const
-	{
-		if( currentTime_ >= endTime_ ) return true;
-		if( abs(currentTime_-endTime_) < 0.5*dt_ )return true;
-		return false;	
-	}
-	bool reachedStopAt()const
-	{
-		if( currentTime_ >= stopAt_ ) return true;
-		if( abs(currentTime_-stopAt_) < 0.5*dt_ )return true;
-		return false;
-	}
+	bool finalTime()const;
+	
+	bool reachedStopAt()const;
 
 	bool outputToFile()const
 	{
diff --git a/src/phasicFlow/repository/systemControl/systemControl.cpp b/src/phasicFlow/repository/systemControl/systemControl.cpp
index eabde21a..4cd60260 100644
--- a/src/phasicFlow/repository/systemControl/systemControl.cpp
+++ b/src/phasicFlow/repository/systemControl/systemControl.cpp
@@ -235,39 +235,43 @@ pFlow::systemControl::systemControl(
 bool pFlow::systemControl::operator ++(int)
 {
 
-	// skip writing to file for the first iteration
-	//output<< "time()++"<<endl;
-	auto finished = time()++; 
-	
-	writeToFileTimer_.start();
-	if(time().currentIter() != 0)
-	{
-		//- save the results to file  
-		if( !time().write() )
-		{
-			fatalErrorInFunction;
-			return false;
-		}
-	}
-	else if( time().finalTime() )
-	{
-		if( !time().write() )
-		{
-			fatalErrorInFunction;
-			return false;
-		}
-	}
-	writeToFileTimer_.end();
+	auto toContinue = time()++;
 
-	//output<< "after finalTime()"<<endl;
+	if(toContinue)
+	{
+		writeToFileTimer_.start();
+		//if(time().currentIter() != 0 )
+		{
+			//- save the results to file  
+			if( !time().write() )
+			{
+				fatalErrorInFunction;
+				return false;
+			}
+		}
+		writeToFileTimer_.end();
 
-	if( time().timersReportTime() &&
+		if( time().timersReportTime() &&
 		timersReport() )
+		{
+			timers_.write(output, true);
+		}
+
+	}
+	else if (time().finalTime())
 	{
+		writeToFileTimer_.start();
+		if( !time().write() )
+		{
+			fatalErrorInFunction;
+			return false;
+		}
+		writeToFileTimer_.end();
+
 		timers_.write(output, true);
 	}
 	
-	return finished;
+	return toContinue;
 }