diff --git a/app/Http/Controllers/BucketController.php b/app/Http/Controllers/BucketController.php
index e5f9997..f2e2341 100644
--- a/app/Http/Controllers/BucketController.php
+++ b/app/Http/Controllers/BucketController.php
@@ -33,6 +33,7 @@ public function store(Request $request, Scenario $scenario): JsonResponse
             'type' => 'required|in:'.implode(',', BucketTypeEnum::values()),
             'allocation_type' => 'required|in:'.implode(',', BucketAllocationTypeEnum::values()),
             'allocation_value' => 'nullable|numeric',
+            'buffer_multiplier' => 'sometimes|nullable|numeric|min:0',
             'priority' => 'nullable|integer|min:1',
         ]);
 
@@ -52,7 +53,8 @@ public function store(Request $request, Scenario $scenario): JsonResponse
                 $allocationType,
                 $type,
                 $validated['allocation_value'] ?? null,
-                $validated['priority'] ?? null
+                $validated['priority'] ?? null,
+                isset($validated['buffer_multiplier']) ? (float) $validated['buffer_multiplier'] : null,
             );
 
             return response()->json([
@@ -74,6 +76,7 @@ public function update(Request $request, Bucket $bucket): JsonResponse
             'type' => 'required|in:'.implode(',', BucketTypeEnum::values()),
             'allocation_type' => 'required|in:'.implode(',', BucketAllocationTypeEnum::values()),
             'allocation_value' => 'nullable|numeric',
+            'buffer_multiplier' => 'sometimes|nullable|numeric|min:0',
             'priority' => 'nullable|integer|min:1',
         ]);
 
@@ -105,6 +108,11 @@ public function update(Request $request, Bucket $bucket): JsonResponse
             $validated['allocation_value'] = null;
         }
 
+        // Buffer only applies to fixed_limit buckets — always reset on type change
+        if ($allocationType !== BucketAllocationTypeEnum::FIXED_LIMIT) {
+            $validated['buffer_multiplier'] = 0.0;
+        }
+
         // Handle priority change if needed
         if (isset($validated['priority']) && $validated['priority'] !== $bucket->priority) {
             $this->updateBucketPriority($bucket, $validated['priority']);
@@ -221,7 +229,8 @@ private function formatBucketResponse(Bucket $bucket): array
             'allocation_type' => $bucket->allocation_type,
             'allocation_value' => $bucket->allocation_value,
             'allocation_type_label' => $bucket->getAllocationTypeLabel(),
-            'formatted_allocation_value' => $bucket->getFormattedAllocationValue(),
+            'buffer_multiplier' => (float) $bucket->buffer_multiplier,
+            'effective_capacity' => $bucket->getEffectiveCapacity(),
             'current_balance' => $bucket->getCurrentBalance(),
             'has_available_space' => $bucket->hasAvailableSpace(),
             'available_space' => $bucket->getAvailableSpace(),
diff --git a/app/Http/Resources/BucketResource.php b/app/Http/Resources/BucketResource.php
index 841d94f..ed08d94 100644
--- a/app/Http/Resources/BucketResource.php
+++ b/app/Http/Resources/BucketResource.php
@@ -19,7 +19,8 @@ public function toArray(Request $request): array
             'allocation_type' => $this->allocation_type,
             'allocation_value' => $this->allocation_value,
             'allocation_type_label' => $this->getAllocationTypeLabel(),
-            'formatted_allocation_value' => $this->getFormattedAllocationValue(),
+            'buffer_multiplier' => (float) $this->buffer_multiplier,
+            'effective_capacity' => $this->getEffectiveCapacity(),
             'current_balance' => $this->getCurrentBalance(),
             'has_available_space' => $this->hasAvailableSpace(),
             'available_space' => $this->getAvailableSpace(),
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 38c065e..02f0b34 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -175,7 +175,13 @@ parameters:
 			path: app/Http/Resources/BucketResource.php
 
 		-
-			message: '#^Call to an undefined method App\\Http\\Resources\\BucketResource\:\:getFormattedAllocationValue\(\)\.$#'
+			message: '#^Access to an undefined property App\\Http\\Resources\\BucketResource\:\:\$buffer_multiplier\.$#'
+			identifier: property.notFound
+			count: 1
+			path: app/Http/Resources/BucketResource.php
+
+		-
+			message: '#^Call to an undefined method App\\Http\\Resources\\BucketResource\:\:getEffectiveCapacity\(\)\.$#'
 			identifier: method.notFound
 			count: 1
 			path: app/Http/Resources/BucketResource.php