diff --git a/src/pocketmine/level/format/anvil/RegionLoader.php b/src/pocketmine/level/format/anvil/RegionLoader.php
index 3ec703896..2a8810b78 100644
--- a/src/pocketmine/level/format/anvil/RegionLoader.php
+++ b/src/pocketmine/level/format/anvil/RegionLoader.php
@@ -160,7 +160,7 @@ class RegionLoader{
 		$writer = new NBT(NBT::BIG_ENDIAN);
 		$nbt->setName("Level");
 		$writer->setData(new Compound("", array("Level" => $nbt)));
-		$chunkData = $writer->writeCompressed(self::COMPRESSION_ZLIB, self::$COMPRESSION_LEVEL);
+		$chunkData = $writer->writeCompressed(ZLIB_ENCODING_DEFLATE, self::$COMPRESSION_LEVEL);
 		$length = strlen($chunkData) + 1;
 		$sectors = (int) ceil(($length + 4) / 4096);
 		$index = self::getChunkOffset($x, $z);
diff --git a/src/pocketmine/nbt/NBT.php b/src/pocketmine/nbt/NBT.php
index 042a6e2fd..d42cbc546 100644
--- a/src/pocketmine/nbt/NBT.php
+++ b/src/pocketmine/nbt/NBT.php
@@ -121,7 +121,7 @@ class NBT{
 
 	public function writeCompressed($compression = ZLIB_ENCODING_GZIP, $level = 7){
 		if(($write = $this->write()) !== false){
-			return zlib_encode($write, ZLIB_ENCODING_GZIP, $level);
+			return zlib_encode($write, $compression, $level);
 		}
 
 		return false;