diff --git a/README.md b/README.md
index a962e86f..b86e04ff 100644
--- a/README.md
+++ b/README.md
@@ -351,6 +351,16 @@ $ node bin/node --fast
 
 `--fast` will enable checkpoints, coin cache, and getheaders.
 
+Some environment variables are available for quick configuration:
+
+- `BCOIN_USE_WORKERS=1` - Enable workers for TX verification.
+- `BCOIN_SEED=[host]` - Use a preferred seed node to connect to.
+- `BCOIN_NETWORK=[network]` - Set the network (main, testnet, regtest, segnet3,
+  or segnet4).
+- `BCOIN_DB=[db-name]` - Default database backend (leveldb, rocksdb, lmdb,
+  memory).
+- `BCOIN_LOGLEVEL=[level]` - Default log level (debug, info, warning, error).
+
 ### Running a full node in the browser
 
 ``` bash
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 66e06340..b38ff054 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -1607,9 +1607,11 @@ Pool.prototype._sendRequests = function _sendRequests(peer) {
     else if (this.chain.height <= 150000)
       size = 250;
     else if (this.chain.height <= 250000)
-      size = 20;
+      size = 150;
+    else if (this.chain.height <= 350000)
+      size = 50;
     else
-      size = 10;
+      size = 20;
 
     if (this.request.activeBlocks >= size)
       return;