Medaka Breeder vs MarimoSimulator
Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.
Medaka Breeder
Experience realistic fish keeping by feeding and cleaning your virtual fish. Watch them grow, breed, and inherit traits from their parents. Customize aquariums and collect various fish species.
- Realistic killifish keeping simulation
- Breed fish and inherit traits
- Customize aquariums with decorations
- Collect over 46 types of killifish
- Missions and rewards system
- Observation and shooting modes
Read full descriptionHide full description
[Game Features] You can experience realistic killifish keeping in your phone. Taking care of your killifish is very easy: just feed them once every three days and clean the tank. The killifish will eventually grow over time and breed with other adult killifish (2cm or larger). The killifish born from the breeding will inherit the characteristics of their parents. A maximum of 50 killifish can be kept. Up to 10 killifish can be kept in one tank, Up to 5 aquariums can be set up. Functions ■Mode switching Default: Information on the killifish and aquarium is displayed, allowing the user to check the status of their care. Observation: Hides the display of information, allowing you to closely observe the aquarium and killifish. You can also tap on the water surface or the aquarium area to see if there is any reaction! Shooting: This function is useful when you want to hide the information and buttons and take pictures of only the killifish and the aquarium. ■Name your killifish You can name each killifish. You can name each killifish so that even if you have a lot of killifish, you will never lose track of them. Layout of the aquarium You can keep your killifish in your favorite decorated aquarium. There are a total of five types of layouts. Layout types: tank appearance, bottom sand, stones, plants, and ornaments. ■ Shop You can purchase killifish, aquariums and ornaments. There are 46 types of killifish sold in the store! ■Missions You can receive rewards by accomplishing various missions. You can purchase more items such as killifish and aquarium tanks by challenging many missions. ■Revival Chance If you are too busy to take care of your killifish and let them die, don't worry! You can bring them back to life with the Resurrection Chance! Premium Pack (paid feature) Clear ads from auto-display. - Eliminate banner ads - Eliminate interstitial ads Relief mode is released (can be switched). - killifish won't die. Useful functions added - Collective feeding - Collective cleaning All items can be purchased Daily mission rewards tripled 50,000 G present
MarimoSimulator
Experience daily relaxation by raising fluffy, cute marimo. Enjoy visual effects by switching lights and soothing music. This simple idle game is perfect for killing time and finding peace.
- Idle marimo breeding
- Relaxing gameplay
- Visual light effects
- Soothing music
- Simple controls
- Tank cleaning mechanic
Read full descriptionHide full description
Easy Idle Breeding Game with Simple Controls ■ Purpose of the App ■ Experience daily relaxation by raising fluffy and cute marimo. Enjoy interesting visual effects by switching the lights. With beautiful graphics and soothing music that make you feel like you're raising marimo in a tank, forget your daily stress and spend peaceful moments. Unlike raising pets, the breeding elements are simple and easy!! Perfect for killing time! Raise marimo and feel the relaxation in your daily life. ■ How to Care for Marimo ■ Caring for marimo is easy. Clean the tank once every 4 days
Screenshots
Verdict
The clearest difference is ads: Medaka Breeder at none against MarimoSimulator's shown. Medaka Breeder also leads on update cadence (every 5 days vs every 3 weeks) and ratings volume (17 vs 2). MarimoSimulator's advantage is rating (5.0 vs 4.6) and review sentiment (83% vs 67%). On price, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
MarimoSimulator holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Medaka Breeder has 17 ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 67% of Medaka Breeder's written reviews are positive against 83% of MarimoSimulator's.
Medaka Breeder ships an update every 5 days, MarimoSimulator every 3 weeks. The most recent releases landed on November 3, 2026 and November 4, 2026 respectively.
| Parameter | Medaka Breeder | MarimoSimulator |
|---|---|---|
| Price | Free | Free |
| Rating | 4.6 (17 ratings) | 5.0 (2 ratings) — better |
| Positive reviews | 66.7% of reviews | 83.3% of reviews — better |
| Number of ratings | 17 — better | 2 |
| Update frequency | Every 5 days — better | Every 3 weeks |
| Ads | No — better | Yes |
| In-app purchases | No | No |
| Monetization | Free with in-app purchases | Ad-supported — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 12.0 — better | 15.0 |
| Further details — not scored | ||
| Size | 91 MB | 289 MB |
| Age rating | 4+ | 4+ |
| Developer | Taiho Yanase | Takuma Takahashi |
Customer experience
Medaka Breeder
MarimoSimulator
In-app purchases
Medaka Breeder
No in-app purchases
MarimoSimulator
No in-app purchases
Questions
Is Medaka Breeder free?
Is MarimoSimulator free?
Which has better reviews, Medaka Breeder or MarimoSimulator?
Do Medaka Breeder or MarimoSimulator have ads?
Which is updated more often, Medaka Breeder or MarimoSimulator?
Other comparisons















