diff --git a/app/src/main/java/com/example/hpostesting/presentation/hemocube/HemoCubeFragment.kt b/app/src/main/java/com/example/hpostesting/presentation/hemocube/HemoCubeFragment.kt
index aae9d13..65f4fac 100644
--- a/app/src/main/java/com/example/hpostesting/presentation/hemocube/HemoCubeFragment.kt
+++ b/app/src/main/java/com/example/hpostesting/presentation/hemocube/HemoCubeFragment.kt
@@ -354,6 +354,14 @@ class HemoCubeFragment : Fragment() {
 //                        }
 //                    }
 //                }
+
+                if (led1Average < 0 || led2Average < 0) {
+                    activity?.runOnUiThread{
+                        binding.errorMessage.text = "Warning: Negative Abs. Retake Blank Reading"
+                        binding.errorMessage.visibility = View.VISIBLE
+                    }
+                }
+
                 DataHolder.hemoCubeTestData?.apply {
                     deviceId = deviceSerialNo
                     led1Buffer = led1BufferForDevice