After completing the Tenacity quests, you trade your Lu Shang rod to Jourdeneaux in Rabao and he will make it +1. Please note you will not get your regular Lu Shang Rod back. Also, he will tell you this rod can break and to bring him ancient lumber to fix it.
East Saurtabaruta F9 Lu Shangs + Shrimp Lure catches Monke-onke. About half the time this fish triggers the RoE 'Catch Size and Weight' under Fishing Tenacity for the Lu Shang's +1 quest if you need it.