diff --git a/cmd/serve.go b/cmd/serve.go
index 5a7c3d20..90f45cd5 100644
--- a/cmd/serve.go
+++ b/cmd/serve.go
@@ -30,6 +30,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/ethereum/go-ethereum/statediff"
+	sdtypes "github.com/ethereum/go-ethereum/statediff/types"
 	"github.com/mailgun/groupcache/v2"
 	log "github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
@@ -304,6 +305,7 @@ func startStateTrieValidator(config *s.Config, server s.Server) {
 
 type WatchedAddress struct {
 	Address      string `db:"address"`
+	Kind         int    `db:"kind"`
 	CreatedAt    uint64 `db:"created_at"`
 	WatchedAt    uint64 `db:"watched_at"`
 	LastFilledAt uint64 `db:"last_filled_at"`
@@ -337,7 +339,15 @@ func startWatchedAddressGapFiller(config *s.Config) {
 			fillAddresses := []interface{}{}
 			for _, fillWatchedAddress := range fillWatchedAddresses {
 				if blockNumber >= fillWatchedAddress.startBlock && blockNumber <= fillWatchedAddress.endBlock {
-					params.WatchedAddresses = append(params.WatchedAddresses, common.HexToAddress(fillWatchedAddress.Address))
+					switch fillWatchedAddress.Kind {
+					case sdtypes.WatchedAddress.Int():
+						params.WatchedAddresses = append(params.WatchedAddresses, common.HexToAddress(fillWatchedAddress.Address))
+					case sdtypes.WatchedStorageSlot.Int():
+						params.WatchedStorageSlots = append(params.WatchedStorageSlots, common.HexToHash(fillWatchedAddress.Address))
+					default:
+						log.Fatalf("Unexpected kind %d:", fillWatchedAddress.Kind)
+					}
+
 					fillAddresses = append(fillAddresses, fillWatchedAddress.Address)
 				}
 			}
@@ -541,6 +551,6 @@ func init() {
 	viper.BindPFlag("validator.everyNthBlock", serveCmd.PersistentFlags().Lookup("validator-every-nth-block"))
 
 	// watched address gap filler flags
-	viper.BindPFlag("watch.fill.enabled", serveCmd.PersistentFlags().Lookup("watch-fill-enabled"))
-	viper.BindPFlag("watch.fill.interval", serveCmd.PersistentFlags().Lookup("watch-fill-interval"))
+	viper.BindPFlag("watch.fill.enabled", serveCmd.PersistentFlags().Lookup("watched-address-gap-filler-enabled"))
+	viper.BindPFlag("watch.fill.interval", serveCmd.PersistentFlags().Lookup("watched-address-gap-filler-interval"))
 }