Update: It was previously stated that the Stardew aquarium mod was made by one person when it actually has been created by a whole team. For a full list of the modders and contributors, check out the credits section listed at the bottom of the mod's page over on Nexus mods.
Story: One thing I love about Stardew Valley is the never-ending collect-a-thon of objects to get and lists to complete. It's something that the life-sim genre goes incredibly well, and one modder has added even more tasks with their Animal Crossing-inspired aquarium mod.
The Stardew Aquarium mod adds an aquarium to the Stardew universe where you can donate fish to fill its empty exhibitions. Every time you donate a fish at the front desk, it will appear in one of the aquarium's many themed rooms and in return, you'll receive prizes every time you donate a certain number of times. The mod even has animations for each fish, so when you explore the aquarium you can see them swimming around happily in their new home.
This new aquarium is in a totally new beach area the mod adds to the game which you can get to by catching the Pelican Town train station. The seaside district includes a large beach, snack shop, wooden pier, ice cream stand, a submarine shop where you can purchase fishing supplies, and the aquarium.
The FAQ says that the mod has been created to be as compatible with as many other mods as possible. For example, if you have a mod installed that adds more species of fish, the mod will still recognise those particular fish as valid donations, which is great.
Head on over to Nexus Mods to download the mod and make sure to read the installation instructions for more details. I'm a little obsessed with installing Stardew Valley mods, especially ones that add new areas to the base game. Two of my favourites are Stray Cat Cafe mod that adds a cosy cafe run by twins, and the Garden Village Shops mod that adds a new shopping district to the Pelican Town bus route.