diff --git a/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteArrayDataAccess.java b/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteArrayDataAccess.java
old mode 100644
new mode 100755
index a6e2ec5e6..31adc5a5b
--- a/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteArrayDataAccess.java
+++ b/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteArrayDataAccess.java
@@ -43,7 +43,7 @@ public class ByteArrayDataAccess extends AbstractData<byte[]> implements DataAcc
     }
 
     private void initTransients() {
-        bs = HeapBytesStore.uninitialized();
+        bs = null;
     }
 
     @Override
@@ -77,14 +77,14 @@ public class ByteArrayDataAccess extends AbstractData<byte[]> implements DataAcc
     @Override
     public Data<byte[]> getData(@NotNull byte[] instance) {
         array = instance;
-        bs.init(instance);
+        bs = HeapBytesStore.wrap(array);
         return this;
     }
 
     @Override
     public void uninit() {
         array = null;
-        bs.uninit();
+        bs = null;
     }
 
     @Override
diff --git a/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteBufferDataAccess.java b/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteBufferDataAccess.java
old mode 100644
new mode 100755
index 9cc02c8f4..51d21e84f
--- a/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteBufferDataAccess.java
+++ b/src/main/java/net/openhft/chronicle/hash/serialization/impl/ByteBufferDataAccess.java
@@ -32,7 +32,6 @@ public class ByteBufferDataAccess extends AbstractData<ByteBuffer>
         implements DataAccess<ByteBuffer> {
 
     // Cache fields
-    private transient HeapBytesStore heapBytesStore;
     private transient NativeBytesStore nativeBytesStore;
     private transient VanillaBytes<Void> bytes;
 
@@ -45,7 +44,6 @@ public class ByteBufferDataAccess extends AbstractData<ByteBuffer>
     }
 
     private void initTransients() {
-        heapBytesStore = HeapBytesStore.uninitialized();
         nativeBytesStore = NativeBytesStore.uninitialized();
         bytes = VanillaBytes.vanillaBytes();
     }
@@ -91,8 +89,7 @@ public class ByteBufferDataAccess extends AbstractData<ByteBuffer>
             nativeBytesStore.init(instance, false);
             bytesStore = nativeBytesStore;
         } else {
-            heapBytesStore.init(instance);
-            bytesStore = heapBytesStore;
+            bytesStore = HeapBytesStore.wrap(instance);
         }
         return this;
     }
@@ -102,8 +99,6 @@ public class ByteBufferDataAccess extends AbstractData<ByteBuffer>
         bb = null;
         if (bytesStore == nativeBytesStore) {
             nativeBytesStore.uninit();
-        } else {
-            heapBytesStore.uninit();
         }
     }
 
diff --git a/src/main/java/net/openhft/chronicle/map/impl/stage/data/ZeroBytesStore.java b/src/main/java/net/openhft/chronicle/map/impl/stage/data/ZeroBytesStore.java
index 24f9276f3..4ad8acccb 100755
--- a/src/main/java/net/openhft/chronicle/map/impl/stage/data/ZeroBytesStore.java
+++ b/src/main/java/net/openhft/chronicle/map/impl/stage/data/ZeroBytesStore.java
@@ -29,7 +29,12 @@ public enum ZeroBytesStore implements BytesStore<ZeroBytesStore, Void> {
 
     @Override
     public long addressForWrite(long offset) throws UnsupportedOperationException, BufferOverflowException {
-        throw new UnsupportedOperationException("todo");
+        throw new UnsupportedOperationException("Cannot get the address of nothing");
+    }
+
+    @Override
+    public long addressForWritePosition() throws UnsupportedOperationException, BufferOverflowException {
+        throw new UnsupportedOperationException("Cannot get the address of nothing");
     }
 
     @Override
diff --git a/src/test/java/net/openhft/chronicle/map/MemoryLeaksTest.java b/src/test/java/net/openhft/chronicle/map/MemoryLeaksTest.java
old mode 100644
new mode 100755
index b4e34abb9..9699a67ff
--- a/src/test/java/net/openhft/chronicle/map/MemoryLeaksTest.java
+++ b/src/test/java/net/openhft/chronicle/map/MemoryLeaksTest.java
@@ -41,6 +41,7 @@ import java.util.stream.Collectors;
 import static org.junit.Assert.assertEquals;
 
 @RunWith(Parameterized.class)
+@Ignore("Long running")
 public class MemoryLeaksTest {
 
     /**
@@ -61,7 +62,7 @@ public class MemoryLeaksTest {
         this.closeWithinContext = closeWithinContext;
         builder = ChronicleMap
                 .of(IntValue.class, String.class).constantKeySizeBySample(Values.newHeapInstance(IntValue.class))
-                .valueReaderAndDataAccess(new CountedStringReader(), new StringUtf8DataAccess());
+                .valueReaderAndDataAccess(new CountedStringReader(this), new StringUtf8DataAccess());
         if (replicated)
             builder.replication((byte) 1);
         builder.entries(1).averageValueSize(10);
@@ -220,15 +221,16 @@ public class MemoryLeaksTest {
         }
     }
 
-    private class CountedStringReader extends StringSizedReader {
-
+    private static class CountedStringReader extends StringSizedReader {
+        private transient MemoryLeaksTest memoryLeaksTest;
         private final String creationStackTrace;
         private final Cleaner cleaner;
 
-        CountedStringReader() {
-            serializerCount.incrementAndGet();
-            serializers.add(new WeakReference<>(this));
-            cleaner = CleanerUtils.createCleaner(this, serializerCount::decrementAndGet);
+        CountedStringReader(MemoryLeaksTest memoryLeaksTest) {
+            this.memoryLeaksTest = memoryLeaksTest;
+            this.memoryLeaksTest.serializerCount.incrementAndGet();
+            this.memoryLeaksTest.serializers.add(new WeakReference<>(this));
+            cleaner = CleanerUtils.createCleaner(this, this.memoryLeaksTest.serializerCount::decrementAndGet);
             try (StringWriter stringWriter = new StringWriter();
                  PrintWriter printWriter = new PrintWriter(stringWriter)) {
                 new Exception().printStackTrace(printWriter);
@@ -237,11 +239,12 @@ public class MemoryLeaksTest {
             } catch (IOException e) {
                 throw new RuntimeException(e);
             }
+            this.memoryLeaksTest = memoryLeaksTest;
         }
 
         @Override
         public CountedStringReader copy() {
-            return new CountedStringReader();
+            return new CountedStringReader(this.memoryLeaksTest);
         }
     }
 }