diff --git a/src/coolant/pump.hpp b/src/coolant/pump.hpp
new file mode 100644
index 0000000..a1f928c
--- /dev/null
+++ b/src/coolant/pump.hpp
@@ -0,0 +1,57 @@
+
+#pragma once
+
+#include <ostream>
+
+namespace sim::coolant
+{
+
+template <class A>
+class pump
+{
+	const double max;
+	const double heat;
+	
+	A* a;
+	double rate = 0;
+
+public:
+
+	constexpr pump(A& a, double max, double heat) : a(&a), max(max), heat(heat)
+	{
+
+	}
+
+	constexpr double get_rate() const
+	{
+		return rate;
+	}
+
+	constexpr double get_flow() const
+	{
+		return rate * max;
+	}
+
+	constexpr void change_speed(double amount)
+	{
+		rate += amount;
+
+		if(rate < 0) rate = 0;
+		if(rate > 1) rate = 1;
+	}
+
+	void update(double secs)
+	{
+		a->add_fluid(rate * max * secs, heat);
+	}
+
+	friend std::ostream& operator<<(std::ostream& o, const pump& p)
+	{
+		o << "Rate: " << (p.get_rate() * 100) << " %\n";
+		o << "Flow: " << (p.get_flow() * 0.001) << " kg/s\n";
+		return o;
+	}
+};
+	
+};
+
diff --git a/src/main.cpp b/src/main.cpp
index 691bdbf..498291c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -7,6 +7,7 @@
 #include "reactor/coolant/vessel.hpp"
 #include "coolant/fluid_t.hpp"
 #include "coolant/valve.hpp"
+#include "coolant/pump.hpp"
 #include "display.hpp"
 
 #include <cmath>
@@ -52,7 +53,8 @@ int main()
 			"#C#C#"
 		});
 
-	sim::coolant::valve<sim::reactor::coolant::vessel> valve(vessel, 1, 101000);
+	sim::coolant::valve<sim::reactor::coolant::vessel> valve(vessel, 1, 500);
+	sim::coolant::pump<sim::reactor::coolant::vessel> pump(vessel, 1e4, 15);
 
 	double secs = 0;
 	long clock = get_now();
@@ -97,13 +99,15 @@ secs:		ss << s << "s\n";
 		{
 			double dt = speed / framerate / steps_extra;
 			reactor.update(rand, dt);
-			vessel.update();
+			pump.update(dt);
 			valve.update(dt);
+			vessel.update();
 			secs += dt;
 		}
 		
 		ss << "Vessel\n" << vessel << "\n";
 		ss << "Steam Valve\n" << valve << "\n";
+		ss << "Coolant Pump\n" << pump << "\n";
 
 		if(do_graphics)
 		{
@@ -185,6 +189,12 @@ secs:		ss << s << "s\n";
 		case 'f':
 			valve.open(-0.001);
 			break;
+		case 'e':
+			pump.change_speed(0.01);
+			break;
+		case 'd':
+			pump.change_speed(-0.01);
+			break;
 		}
 
 		if(do_clock)
diff --git a/src/reactor/coolant/vessel.cpp b/src/reactor/coolant/vessel.cpp
index 0c154a7..0e83547 100644
--- a/src/reactor/coolant/vessel.cpp
+++ b/src/reactor/coolant/vessel.cpp
@@ -52,13 +52,31 @@ double vessel::add_heat(double t1)
 {
 	double t2 = get_heat();
 	double t = t1 - t2;
-	double m1 = 1000000;
+	double m1 = 1e6;
 	double m2 = (fluid.l_to_g(level) + steam) * fluid.jPgk;
 	double m = m1 + m2;
 	
    	return heat = t1 - t * m2 / m;
 }
 
+double vessel::add_fluid(double m2, double t2)
+{
+	double m1 = get_mass();
+	double t1 = get_heat();
+	double t = t1 - t2;
+
+	m2 = fluid.g_to_l(m2);
+
+	if(level + m2 > volume)
+	{
+		m2 = volume - level;
+	}
+
+	heat = t1 - t * m2 / (m1 + m2);
+	level += m2;
+	return m2;
+}
+
 double vessel::extract_steam(double dt, double a, double p2)
 {
 	// calculate the mass moved
diff --git a/src/reactor/coolant/vessel.hpp b/src/reactor/coolant/vessel.hpp
index e6d575f..13c2f6a 100644
--- a/src/reactor/coolant/vessel.hpp
+++ b/src/reactor/coolant/vessel.hpp
@@ -23,12 +23,14 @@ public:
 
 	void update();
 	double add_heat(double amount);
+	double add_fluid(double amount, double heat);
 	double extract_steam(double dt, double a, double p2);
 
 	constexpr double get_volume() const { return volume; }
 	constexpr double get_level() const { return level; }
 	constexpr double get_heat() const { return heat; }
 	constexpr double get_steam() const { return steam; }
+	constexpr double get_mass() const { return fluid.l_to_g(level) + steam; }
 	
 	double get_pressure() const;
 };
diff --git a/src/reactor/rod.cpp b/src/reactor/rod.cpp
index 8b5ed22..75b02c5 100644
--- a/src/reactor/rod.cpp
+++ b/src/reactor/rod.cpp
@@ -45,7 +45,7 @@ void rod::interact(rod* o, double secs)
 double rod::get_speed() const
 {
 	int m = motion < 0 ? -1 : 1;
-	return motion == 0 ? 0 : (std::pow(10, std::abs(motion)) * 1e-10 * m);
+	return motion == 0 ? 0 : (std::pow(10, std::abs(motion)) * 1e-6 * m);
 }
 
 void rod::update_rod(double secs)
@@ -70,7 +70,7 @@ void rod::update_rod_selected(int m)
 {
 	motion += m;
 
-	if(motion > 10) motion = 10;
-	if(motion < -10) motion = -10;
+	if(motion > 5) motion = 5;
+	if(motion < -5) motion = -5;
 }