# marimo vs Medaka Aquarium Breeder

The clearest difference is ads: marimo at none against Medaka Aquarium Breeder's shown. marimo also leads on monetization model (free vs ad-supported) and iOS requirement (9.0 vs 13.3). Medaka Aquarium Breeder's advantage is update cadence (every 11 days vs every 4 months). On price, review sentiment, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

marimo ships an update every 4 months, Medaka Aquarium Breeder every 11 days. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | marimo | Medaka Aquarium Breeder |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.3 (3 ratings)](https://appshunter.io/ios/app/medaka-aquarium-breeder/id6466660802/reviews)** |
| Number of ratings | — | **3** |
| Positive reviews | 98.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 4 months | **Every 11 days** |
| Monetization | **Free** | Ad-supported |
| Size | 31 MB | 244 MB |
| Requires iOS | **9.0** | 13.3 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [HANA-DA Hiromitsu](https://appshunter.io/developer/392896308) | [Yuki Naruse](https://appshunter.io/developer/1707604115) |

## What reviewers say

### marimo

[App page](https://appshunter.io/ios/app/marimo/id392896305)

A virtual pet simulation where you nurture a Marimo, a unique aquatic plant from Hokkaido. The core gameplay involves changing its water to help it grow. You can then share your Marimo's progress with friends.

**Highlights:** Virtual Marimo pet, Water changing gameplay, Marimo growth simulation, Share progress on Twitter, Hokkaido souvenir theme

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Medaka Aquarium Breeder

[App page](https://appshunter.io/ios/app/medaka-aquarium-breeder/id6466660802)

Raise and breed killifish in a relaxing aquarium simulation. Manage water quality, feed your fish, and sell them to upgrade your tank. Discover new species and create a beautiful underwater world.

**Highlights:** Manage aquarium water quality and temperature, Feed and grow killifish, Sell fish to earn money, Breed new killifish species, Customize aquarium with equipment and layouts, Offline play available

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is marimo free?

marimo is free to download, with no in-app purchases.

### Is Medaka Aquarium Breeder free?

Medaka Aquarium Breeder is free to download, with no in-app purchases.

### Do marimo or Medaka Aquarium Breeder have ads?

Medaka Aquarium Breeder shows ads; marimo does not.

### Which is updated more often, marimo or Medaka Aquarium Breeder?

marimo ships an update every 4 months, and Medaka Aquarium Breeder every 11 days. Most recently, marimo was updated on November 1, 2026 and Medaka Aquarium Breeder on November 3, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*