diff --git a/libraries/chain/steem_evaluator.cpp b/libraries/chain/steem_evaluator.cpp
index 7ce03b8655..48694c2cbe 100644
--- a/libraries/chain/steem_evaluator.cpp
+++ b/libraries/chain/steem_evaluator.cpp
@@ -621,7 +621,15 @@ void comment_evaluator::do_apply( const comment_operation& o )
             FC_ASSERT( _db.calculate_discussion_payout_time( *parent ) != fc::time_point_sec::maximum(), "Discussion is frozen." );
       }
 
-      if( _db.has_hardfork( STEEM_HARDFORK_0_12__176 ) )
+      FC_TODO( "Cleanup this logic after HF 20. Old ops don't need to check pre-hf20 times." )
+      if( _db.has_hardfork( STEEM_HARDFORK_0_20__2019 ) )
+      {
+         if( o.parent_author == STEEM_ROOT_POST_PARENT )
+             FC_ASSERT( ( now - auth.last_root_post ) > STEEM_MIN_ROOT_COMMENT_INTERVAL, "You may only post once every 5 minutes.", ("now",now)("last_root_post", auth.last_root_post) );
+         else
+             FC_ASSERT( (now - auth.last_post) >= STEEM_MIN_REPLY_INTERVAL_HF20, "You may only comment once every 3 seconds.", ("now",now)("auth.last_post",auth.last_post) );
+      }
+      else if( _db.has_hardfork( STEEM_HARDFORK_0_12__176 ) )
       {
          if( o.parent_author == STEEM_ROOT_POST_PARENT )
              FC_ASSERT( ( now - auth.last_root_post ) > STEEM_MIN_ROOT_COMMENT_INTERVAL, "You may only post once every 5 minutes.", ("now",now)("last_root_post", auth.last_root_post) );
diff --git a/libraries/protocol/get_config.cpp b/libraries/protocol/get_config.cpp
index 179c5b4e32..25018a36c6 100644
--- a/libraries/protocol/get_config.cpp
+++ b/libraries/protocol/get_config.cpp
@@ -131,6 +131,7 @@ fc::variant_object get_config()
    result["STEEM_MIN_CURATE_REWARD"] = STEEM_MIN_CURATE_REWARD;
    result["STEEM_MIN_PERMLINK_LENGTH"] = STEEM_MIN_PERMLINK_LENGTH;
    result["STEEM_MIN_REPLY_INTERVAL"] = STEEM_MIN_REPLY_INTERVAL;
+   result["STEEM_MIN_REPLY_INTERVAL_HF20"] = STEEM_MIN_REPLY_INTERVAL_HF20;
    result["STEEM_MIN_ROOT_COMMENT_INTERVAL"] = STEEM_MIN_ROOT_COMMENT_INTERVAL;
    result["STEEM_MIN_VOTE_INTERVAL_SEC"] = STEEM_MIN_VOTE_INTERVAL_SEC;
    result["STEEM_MINER_ACCOUNT"] = STEEM_MINER_ACCOUNT;
diff --git a/libraries/protocol/hardfork.d/0_20.hf b/libraries/protocol/hardfork.d/0_20.hf
index edb8d06c99..ce73502ef1 100644
--- a/libraries/protocol/hardfork.d/0_20.hf
+++ b/libraries/protocol/hardfork.d/0_20.hf
@@ -11,6 +11,7 @@
 #define STEEM_HARDFORK_0_20__1782 (STEEM_HARDFORK_0_20)
 #define STEEM_HARDFORK_0_20__1811 (STEEM_HARDFORK_0_20)
 #define STEEM_HARDFORK_0_20__1815 (STEEM_HARDFORK_0_20)
+#define STEEM_HARDFORK_0_20__2019 (STEEM_HARDFORK_0_20)
 
 #define STEEM_HARDFORK_0_20_VERSION hardfork_version( 0, 20 )
 
diff --git a/libraries/protocol/include/steem/protocol/config.hpp b/libraries/protocol/include/steem/protocol/config.hpp
index 3c48d9d376..3efe44398e 100644
--- a/libraries/protocol/include/steem/protocol/config.hpp
+++ b/libraries/protocol/include/steem/protocol/config.hpp
@@ -114,6 +114,7 @@
 
 #define STEEM_MIN_ROOT_COMMENT_INTERVAL       (fc::seconds(60*5)) // 5 minutes
 #define STEEM_MIN_REPLY_INTERVAL              (fc::seconds(20)) // 20 seconds
+#define STEEM_MIN_REPLY_INTERVAL_HF20         (fc::seconds(3)) // 3 seconds
 #define STEEM_POST_AVERAGE_WINDOW             (60*60*24u) // 1 day
 #define STEEM_POST_WEIGHT_CONSTANT            (uint64_t(4*STEEM_100_PERCENT) * (4*STEEM_100_PERCENT))// (4*STEEM_100_PERCENT) -> 2 posts per 1 days, average 1 every 12 hours