diff --git a/tests/LiveRecorder.Tests/StorageGuardServiceTests.cs b/tests/LiveRecorder.Tests/StorageGuardServiceTests.cs
index 8c9b4f7..4ebfa79 100644
--- a/tests/LiveRecorder.Tests/StorageGuardServiceTests.cs
+++ b/tests/LiveRecorder.Tests/StorageGuardServiceTests.cs
@@ -83,13 +83,16 @@ public sealed class StorageGuardServiceTests
     [Fact]
     public void RedPercentageTier_DoesNotBlockFinalizeWhenAbsoluteTemporarySpaceIsAvailable()
     {
+        var service = new StorageGuardService(
+            NullLogger<StorageGuardService>.Instance,
+            new FixedStorageCapacityProvider(totalBytes: 1_000, availableBytes: 800));
         var settings = CreateSettings(enableStorageGuard: true);
         settings.PauseRecordingWhenFreeSpaceBelowMegabytes = 0;
         settings.ResumeRecordingWhenFreeSpaceAboveMegabytes = 0;
         settings.StorageGreenThresholdPercent = 90;
         settings.StorageRedThresholdPercent = 85;
 
-        var result = _service.CheckCanFinalize(settings, estimatedTemporaryBytes: 1);
+        var result = service.CheckCanFinalize(settings, estimatedTemporaryBytes: 1);
 
         Assert.Equal(StorageTier.Red, result.Tier);
         Assert.True(result.HasEnoughSpace);
@@ -132,4 +135,10 @@ public sealed class StorageGuardServiceTests
         StorageGreenThresholdPercent = 30,
         StorageRedThresholdPercent = 10
     };
+
+    private sealed class FixedStorageCapacityProvider(long totalBytes, long availableBytes) : IStorageCapacityProvider
+    {
+        public StorageVolumeCapacity GetCapacity(string outputPath) =>
+            new(Path.GetPathRoot(outputPath) ?? "/", totalBytes, availableBytes);
+    }
 }