diff --git a/lib/services/address/index.js b/lib/services/address/index.js
index a580d4f5..fde98884 100644
--- a/lib/services/address/index.js
+++ b/lib/services/address/index.js
@@ -76,8 +76,20 @@ AddressService.prototype.getAddressHistory = function(addresses, options, callba
       return callback(err);
     }
 
-    options.txIdList = lodash.uniqWith(options.txIdList, lodash.isEqual);
-    options.txIdList = lodash.orderBy(options.txIdList, ['height'], ['desc']);
+    var unique = {};
+    var list = [];
+
+    for (let i = 0; i < options.txIdList.length; i++) {
+      unique[options.txIdList[i].txid + options.txIdList[i].height] = options.txIdList[i];
+    }
+
+    for (var prop in unique) {
+      list.push(unique[prop]);
+    }
+
+    options.txIdList = list.sort(function(a, b) {
+     return b.height - a.height;
+    });
 
     self._getAddressTxHistory(options, function(err, txList) {
 
diff --git a/lib/services/db/index.js b/lib/services/db/index.js
index 854085ff..ecda6d08 100644
--- a/lib/services/db/index.js
+++ b/lib/services/db/index.js
@@ -82,7 +82,6 @@ DB.prototype.start = function(callback) {
     keyEncoding: 'binary',
     valueEncoding: 'binary',
     writeBufferSize: 8 * 1024 * 1024,
-    maxOpenFiles: 3000,
     cacheSize: 1024 * 1024 * 1024 // 1 GB of memory for cache.
   });
 
diff --git a/lib/services/mempool/index.js b/lib/services/mempool/index.js
index 077ef6a6..150e12ca 100644
--- a/lib/services/mempool/index.js
+++ b/lib/services/mempool/index.js
@@ -210,7 +210,6 @@ MempoolService.prototype._getAddressOperations = function(tx, reverse) {
 };
 
 MempoolService.prototype._onTransaction = function(tx) {
-
   var self = this;
   var ops = [{
       type: 'put',