diff --git a/candle.go b/candle.go
index 85d209c..77c7860 100644
--- a/candle.go
+++ b/candle.go
@@ -534,7 +534,9 @@ func (cl *Candle) SetToKey(core *Core) ([]interface{}, error) {
 		logrus.Error("err of PeriodToMinutes:", err)
 	}
 	// expf := float64(exp) * 60
-	expf := float64(exp) * 300
+	length, _ := core.Cfg.Config.Get("sortedSet").Get("length").String()
+	ln := ToFloat64(length)
+	expf := float64(exp) * ln
 	extt := time.Duration(expf) * time.Minute
 	curVolstr, _ := data[5].(string)
 	curVol, err := strconv.ParseFloat(curVolstr, 64)
diff --git a/core.go b/core.go
index 879d382..a5c6917 100644
--- a/core.go
+++ b/core.go
@@ -699,7 +699,9 @@ func (cr *Core) GetExpiration(per string) (time.Duration, error) {
 		return 0, err
 	}
 	exp, err := cr.PeriodToMinutes(per)
-	dur := time.Duration(exp*300) * time.Minute
+	length, _ := cr.Cfg.Config.Get("sortedSet").Get("length").String()
+	ln := ToInt64(length)
+	dur := time.Duration(exp*ln) * time.Minute
 	return dur, err
 }