diff --git a/conf/modules.config b/conf/modules.config
index d6ee1d73..507e475f 100644
--- a/conf/modules.config
+++ b/conf/modules.config
@@ -257,7 +257,7 @@ process {
     }
 
     withName: MEGAHIT {
-        ext.args   = { params.megahit_options ? params.megahit_options + " -m ${task.memory.toBytes()}" : " -m ${task.memory.toBytes()}" }
+        ext.args   = { params.megahit_options ? params.megahit_options + " -m ${task.memory.toBytes()}" : "-m ${task.memory.toBytes()}" }
         ext.prefix = { "MEGAHIT-${meta.id}" }
         publishDir = [path: { "${params.outdir}/Assembly/MEGAHIT" }, mode: params.publish_dir_mode, pattern: "*.{fa.gz,log}"]
     }