Tranquil Koi lets you build and manage an expanding koi empire, starting from a modest pond and scaling up through breeding, selling, and decorating. You'll unlock over 100 koi varieties and customize your aquatic spaces with decorations while earning increasingly large profits from your fish sales. It's best suited for players who enjoy idle games with a gentle pace and visual progression rather than those seeking detailed graphics or fast-paced action.
About this game
Tranquil Koi is a relaxing idle game. Start with a humble pond and transform it into a breathtaking koi paradise! Buy and unlock over 100 vibrant breeds, raise them and sell them to grow your aquatic haven. Unlock decorations to design an aquarium that reflects your vision of tranquility.
What players are saying
▲ Recommended43 hrs
WOW, I'm the first reviewer! I LOVE this game for 3 reasons (listed below). I remember when a demo of this first launched on Itchio and you could play the demo in browser without certain effects, I had this running for hours and hours, I only stopped because my browser could not handle all the fish. As soon as this launched on Steam I bought it, day one. For the price you're getting a very unique zen calm experience.
#1: It's Unique. Tranquil Koi isn't really a clicker type game. You can right click and drop food and feed the Koi fish to make them mature faster but that's not really the point of the game.
#2: It teaches and enforces patience. You don't sit there and click. You buy fish, step away, get some work done, and come back to sell the matured fish.
#3 The long term feeling of progress as you collect all the hundreds of different Koi fish. And there are hundreds of different fish, all uniquely modeled.
===== Suggestions ===== It needs optimization, I've got 60 fish and water reflections and I'm noticing the game starting to slow down. It might be because the code for all the fish are constantly searching for food. Maybe code their AI so that they only search for food when you drop it, and only the fish closest to the food notices and starts swimming in that direction? Or maybe change their animations to use vertex animation.
There's a glitch, I cannot turn off the water and effects. Using the menu to lower them to zero doesn't work, saving and exiting also doesn't work, and doesn't save your settings, but it does save all your progress.
Sorting the fish based on how long they will take to mature would be great. I want to see all my active Koi fish in the list with (23 minutes remaining, 12 minutes remaining etc... for each fish)
Some of the Koi fish are so beautiful I don't want to sell them. There should be a new feature called "My personal Pond" where you can send your favorite fish instead of selling them, so you can keep them.
Add more music. There's a lot of great non-copyrighted calm music all over the internet. You should add it to the game to give more variation to the sound track. Or you can use AI to generate some really amazing nice ambient tracks using Suno.ai.
Anyway thank you so much for this game. It's great, affordable, and so relaxing to have running in the background.
the last update has improved things for me visually and I had a bit of fun today with new koi, location changes looking forward to more fun like this
original: what you see on the sales images is exactly what you get okay for many but disappointment for me fish are so small that you can't see the details of them while swimming I was hoping for more in terms of quality of images, everything really the interface is fine but a bit confusing I'm waiting for some updates otherwise my koi, which I love irl, will sit idle without me
Hello everyone!A new update on the game! New Save System A new saving system to improve stability was redesigned. Please note that existing save files will unfortunately be lost and cannot be backed up due to these changes. Performance Upgrade A large portion of the game code has been simplified and optimized, roughly a 30% FPS boost for most setups. The game should now feel noticeably smoother. Economy Rebalance The in-game economy has been adjusted:Koi fish are now generally cheaperKoi fish grow faster, helping you progress quickerAlso upgrades and decoration prices are rebalancedThank you for your continued support and feedback and happy fish keeping!Recently, I’ve found myself pulled into developing a new horror game, which has slowed updates for this project — thank you for your patience. I’ll be sharing news about the horror game here as well, although I expect the overlap between the two audiences to be fairly small.
Hey guys!Here's the new hot fix #2:· fixed game won't idle during the offline time.· fixed some inaccurate math that caused fish aging incorrectly· unified the old date string with new unix time in the game saving· fixed game music volume wasn't being saved correctly· added the macos 64 version of the gameThe Update is scheduled to be released at 10am GMT 17th nov 2025.
Hot fix #1 Here comes our first hot fix #1:· fixed sometimes language not changed properly· fixed in the fish card container when buying card again the old color won't disappear.· fixed some fish not age correctly· minor assets hue or saturation changes
Posts come from Steam's official announcements feed.