diff --git a/src/main/java/com/commafeed/backend/DatabaseCleaner.java b/src/main/java/com/commafeed/backend/DatabaseCleaner.java
index 4fbbbdeb..75a64bd6 100644
--- a/src/main/java/com/commafeed/backend/DatabaseCleaner.java
+++ b/src/main/java/com/commafeed/backend/DatabaseCleaner.java
@@ -75,15 +75,19 @@ public class DatabaseCleaner {
 		long total = 0;
 		int deleted = -1;
 		do {
-			List<FeedCount> fcs = feedDAO.findDuplicates(0, 1, 1);
+			List<FeedCount> fcs = feedDAO.findDuplicates(0, 10, 1);
 			deleted = fcs.size();
-			for (FeedCount fc : fcs) {
-				Feed into = feedDAO.findById(fc.feeds.get(0).getId());
-				List<Feed> feeds = Lists.newArrayList();
-				for (Feed feed : fc.feeds) {
-					feeds.add(feedDAO.findById(feed.getId()));
-				}
-				mergeFeeds(into, feeds);
+			for (final FeedCount fc : fcs) {
+				new Thread() {
+					public void run() {
+						Feed into = feedDAO.findById(fc.feeds.get(0).getId());
+						List<Feed> feeds = Lists.newArrayList();
+						for (Feed feed : fc.feeds) {
+							feeds.add(feedDAO.findById(feed.getId()));
+						}
+						mergeFeeds(into, feeds);
+					};
+				}.start();
 			}
 			total += deleted;
 			log.info("merged {} feeds", total);