diff --git a/src/Simulator/FloodyFluidSimulator.cpp b/src/Simulator/FloodyFluidSimulator.cpp
index 48655afb3..03e94e791 100644
--- a/src/Simulator/FloodyFluidSimulator.cpp
+++ b/src/Simulator/FloodyFluidSimulator.cpp
@@ -64,8 +64,10 @@ void cFloodyFluidSimulator::SimulateBlock(cChunk * a_Chunk, int a_RelX, int a_Re
 		return;
 	}
 
+	// When in contact with water, lava should harden
 	if (HardenBlock(a_Chunk, a_RelX, a_RelY, a_RelZ, MyBlock, MyMeta))
 	{
+		// Block was changed, bail out
 		return;
 	}
 
diff --git a/src/Simulator/FloodyFluidSimulator.h b/src/Simulator/FloodyFluidSimulator.h
index c0ccd422f..632de3bb2 100644
--- a/src/Simulator/FloodyFluidSimulator.h
+++ b/src/Simulator/FloodyFluidSimulator.h
@@ -47,7 +47,10 @@ protected:
 	/** Checks if there are enough neighbors to create a source at the coords specified; turns into source and returns true if so. */
 	bool CheckNeighborsForSource(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_RelZ);
 
-	/** Check if block should harden (Water/Lava interaction) */
+	/** Checks if the specified block should harden (Water/Lava interaction) and if so, converts it to a suitable block.
+	 *
+	 * Returns whether the block was changed or not.
+	 */
 	bool HardenBlock(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta);
 
 	/** Spread water to neighbors.