diff --git a/ClosedXML/Excel/ConditionalFormats/Save/XLCFColorScaleConverter.cs b/ClosedXML/Excel/ConditionalFormats/Save/XLCFColorScaleConverter.cs
index 5d970d5..6f38667 100644
--- a/ClosedXML/Excel/ConditionalFormats/Save/XLCFColorScaleConverter.cs
+++ b/ClosedXML/Excel/ConditionalFormats/Save/XLCFColorScaleConverter.cs
@@ -7,20 +7,26 @@
 
 namespace ClosedXML.Excel
 {
-    internal class XLCFColorScaleConverter:IXLCFConverter
+    internal class XLCFColorScaleConverter : IXLCFConverter
     {
         public ConditionalFormattingRule Convert(IXLConditionalFormat cf, Int32 priority, XLWorkbook.SaveContext context)
         {
             var conditionalFormattingRule = new ConditionalFormattingRule { Type = cf.ConditionalFormatType.ToOpenXml(), Priority = priority };
-            
+
             var colorScale = new ColorScale();
-            for(Int32 i = 1; i <= cf.Values.Count; i++)
+            for (Int32 i = 1; i <= cf.ContentTypes.Count; i++)
             {
-                var conditionalFormatValueObject = new ConditionalFormatValueObject { Type = cf.ContentTypes[i].ToOpenXml(), Val = cf.Values[i].Value };
+                var type = cf.ContentTypes[i].ToOpenXml();
+                var val = (cf.Values.ContainsKey(i) && cf.Values[i] != null) ? cf.Values[i].Value : null;
+
+                var conditionalFormatValueObject = new ConditionalFormatValueObject { Type = type };
+                if (val != null)
+                    conditionalFormatValueObject.Val = val;
+
                 colorScale.Append(conditionalFormatValueObject);
             }
 
-            for (Int32 i = 1; i <= cf.Values.Count; i++)
+            for (Int32 i = 1; i <= cf.Colors.Count; i++)
             {
                 Color color = new Color { Rgb = cf.Colors[i].Color.ToHex() };
                 colorScale.Append(color);
diff --git a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMax.cs b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMax.cs
index 64614d8..7fdf8de 100644
--- a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMax.cs
+++ b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMax.cs
@@ -22,7 +22,9 @@
         }
         public void HighestValue(XLColor color)
         {
-            Maximum(XLCFContentType.Maximum, "0", color);
+            _conditionalFormat.Values.Add(null);
+            _conditionalFormat.Colors.Add(color);
+            _conditionalFormat.ContentTypes.Add(XLCFContentType.Maximum);
         }
     }
 }
diff --git a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMid.cs b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMid.cs
index 13c31ec..d868a73 100644
--- a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMid.cs
+++ b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMid.cs
@@ -30,7 +30,9 @@
         }
         public void HighestValue(XLColor color)
         {
-            Midpoint(XLCFContentType.Maximum, "0", color);
+            _conditionalFormat.Values.Initialize(null);
+            _conditionalFormat.Colors.Add(color);
+            _conditionalFormat.ContentTypes.Add(XLCFContentType.Maximum);
         }
     }
 }
diff --git a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMin.cs b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMin.cs
index 0c33c04..9f2b647 100644
--- a/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMin.cs
+++ b/ClosedXML/Excel/ConditionalFormats/XLCFColorScaleMin.cs
@@ -27,7 +27,10 @@
 
         public IXLCFColorScaleMid LowestValue(XLColor color)
         {
-            return Minimum(XLCFContentType.Minimum, "0", color);
+            _conditionalFormat.Values.Initialize(null);
+            _conditionalFormat.Colors.Initialize(color);
+            _conditionalFormat.ContentTypes.Initialize(XLCFContentType.Minimum);
+            return new XLCFColorScaleMid(_conditionalFormat);
         }
     }
 }
diff --git a/ClosedXML/Excel/XLWorkbook_Load.cs b/ClosedXML/Excel/XLWorkbook_Load.cs
index d3b05dc..b16b063 100644
--- a/ClosedXML/Excel/XLWorkbook_Load.cs
+++ b/ClosedXML/Excel/XLWorkbook_Load.cs
@@ -1534,6 +1534,8 @@
                     conditionalFormat.ContentTypes.Add(c.Type.Value.ToClosedXml());
                 if (c.Val != null)
                     conditionalFormat.Values.Add(new XLFormula { Value = c.Val.Value });
+                else
+                    conditionalFormat.Values.Add(null);
 
                 if (c.GreaterThanOrEqual != null)
                     conditionalFormat.IconSetOperators.Add(c.GreaterThanOrEqual.Value ? XLCFIconSetOperator.EqualOrGreaterThan : XLCFIconSetOperator.GreaterThan);