# Sim Aquarium vs Koitopia

The clearest difference is rating: Sim Aquarium at 4.1 against Koitopia's 2.3. Sim Aquarium also leads on review sentiment (79% vs 47%) and update cadence (every 10 days vs every 5 weeks). Koitopia's advantage is ads (none vs shown) and iOS requirement (13.0 vs 15.0). On price, ratings volume, in-app purchases and monetization model there is nothing between them.

Both are free to download. Sim Aquarium sells 10 one-off in-app purchases and Koitopia sells 5 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

Sim Aquarium holds the better App Store score, 4.1 against 2.3. Both are backed by a comparable volume of ratings — 17 and 18 respectively. Written reviews point the same way: 79% of Sim Aquarium's written reviews are positive against 47% of Koitopia's.

Sim Aquarium ships an update every 10 days, Koitopia every 5 weeks. The most recent releases landed on October 23, 2026 and October 21, 2026 respectively.

## The numbers

| Metric | Sim Aquarium | Koitopia |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.1 (17 ratings)](https://appshunter.io/ios/app/sim-aquarium-3d-fish-tank/id1050519228/reviews)** | [2.3 (18 ratings)](https://appshunter.io/ios/app/koitopia/id6474526850/reviews) |
| Number of ratings | 17 | **18** |
| Positive reviews | **78.9% of reviews** | 47.1% of reviews |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | **Every 10 days** | Every 5 weeks |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 207 MB | 352 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [达 雷](https://appshunter.io/developer/599274737) | [Homeworx Consulting Pty Ltd](https://appshunter.io/developer/1721842903) |

## What reviewers say

### Sim Aquarium

[App page](https://appshunter.io/ios/app/sim-aquarium-3d-fish-tank/id1050519228)

Create and manage your own 3D aquarium, raising fish from babies to adults. Customize your underwater world with vibrant backgrounds and decorations, and interact with friends' aquariums. Buy, sell, and collect a variety of marine life.

**Highlights:** Buy, raise, and sell fish, Create fish collections, Customize aquariums with backgrounds and decor, Explore a 3D aquatic world, Interact with friends via Game Center and Facebook

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pile of Gems | $1.99 | one-time |
| Mound of Gems | $4.99 | one-time |
| Aquarium Special Pack | $4.99 | one-time |
| Bag of Gems | $9.99 | one-time |
| Rare Crab Breeding Pack | $9.99 | one-time |
| Sack of Gems | $19.99 | one-time |
| Super Aquarium Pack | $19.99 | one-time |
| Basket of Gems | $29.99 | one-time |
| Box of Gems | $49.99 | one-time |
| Chest of Gems | $99.99 | one-time |

**What reviewers like**

- 🎨 Beautiful graphics and animation
- 😌 Relaxing and calming gameplay
- 🐠 Realistic and cute fish
- 💡 Interesting concept and gameplay
- 🏠 Customizable aquariums

**What reviewers complain about**

- 💥 Frequent crashes
- 💸 Expensive in-app purchases
- ⏳ Slow progression and hard goals
- 🚫 Ads are irritating
- ❓ Glitches and bugs

**Reported bugs**

- Game crashes frequently
- Game refuses to open or load
- Purchased items not received
- Game frozen
- Missing gems/rewards

**Requested features**

- More levels
- More fish breeds and decorations
- More challenges
- Option to remove ads
- Ability to email/message developers


### Koitopia

[App page](https://appshunter.io/ios/app/koitopia/id6474526850)

Breed and grow unique Koi varieties in a virtual pond. Complete quests, solve puzzles, and customize your environment. Showcase your prized fish in this relaxing 3D simulation game.

**Highlights:** Koi breeding mechanics, Pond customization, Daily quests and puzzles, Event-based challenges, Mini-games (Feed the Fish, Catch the Food), Ornamental Pond showcase

**Features:** macOS Compatibility

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Water Koi Fortune Pack | $0.99 | one-time |
| Koi Spring Bundle | $4.99 | one-time |
| Koi Ripples Cache | $9.99 | one-time |
| Koi Tranquility Collection | $24.99 | one-time |
| Koi Floating World Trove | $79.99 | one-time |


## Frequently asked questions

### Is Sim Aquarium free?

Sim Aquarium is free to download, with in-app purchases available.

### Is Koitopia free?

Koitopia is free to download, with in-app purchases available.

### Which has better reviews, Sim Aquarium or Koitopia?

Sim Aquarium is rated higher. Sim Aquarium averages 4.1 out of 5 from 17 ratings, while Koitopia averages 2.3 from 18 ratings.

### Do Sim Aquarium or Koitopia have ads?

Sim Aquarium shows ads; Koitopia does not.

### Which is updated more often, Sim Aquarium or Koitopia?

Sim Aquarium ships an update every 10 days, and Koitopia every 5 weeks. Most recently, Sim Aquarium was updated on October 23, 2026 and Koitopia on October 21, 2026.

---

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