Catch Cook Eel in Stardew Valley Expert Tips GuideCosmic heart fish is a valuable catch in the Stardew Valley game. This lovable eel can be found in the river during wet weather and at night. If you manage to hook a Stardew eel, you can sell it for a decent sum of money. In addition to its monetary value, it is also in demand by anglers for its captivating charm. So, grab your tackle box and head to the streamside to try your luck at catching this Stardew eel. Happy fishing!