diff --git a/pom.xml b/pom.xml
index b57a4d0..5766363 100644
--- a/pom.xml
+++ b/pom.xml
@@ -65,7 +65,7 @@
         <!-- Do not change unless you want different name for local builds. -->
         <build.number>-LOCAL</build.number>
         <!-- This allows to change between versions. -->
-        <build.version>2.8.1</build.version>
+        <build.version>2.9.0</build.version>
         <sonar.projectKey>BentoBoxWorld_Level</sonar.projectKey>
         <sonar.organization>bentobox-world</sonar.organization>
         <sonar.host.url>https://sonarcloud.io</sonar.host.url>
diff --git a/src/main/java/world/bentobox/level/calculators/IslandLevelCalculator.java b/src/main/java/world/bentobox/level/calculators/IslandLevelCalculator.java
index 2a1ac3a..845ba5c 100644
--- a/src/main/java/world/bentobox/level/calculators/IslandLevelCalculator.java
+++ b/src/main/java/world/bentobox/level/calculators/IslandLevelCalculator.java
@@ -433,7 +433,7 @@ public class IslandLevelCalculator {
                     continue;
                 }
                 // Only count to the highest block in the world for some optimization
-                for (int y = 0; y < chunk.getWorld().getMaxHeight(); y++) {
+                for (int y = chunk.getWorld().getMinHeight(); y < chunk.getWorld().getMaxHeight(); y++) {
                     BlockData blockData = chunkSnapshot.getBlockData(x, y, z);
                     boolean belowSeaLevel = seaHeight > 0 && y <= seaHeight;
                     // Slabs can be doubled, so check them twice