# Reef Book vs Reef Diary Aquarium Management

The clearest difference is price: Reef Diary Aquarium Management at Free against Reef Book's $5.99. Reef Diary Aquarium Management also leads on update cadence (monthly vs every 6 months) and iOS requirement (15.1 vs 26.0). Reef Book's advantage is in-app purchases (none vs 4). On ads and device support there is nothing between them.

Reef Diary Aquarium Management is free to download; Reef Book costs $5.99 up front. Reef Diary Aquarium Management sells 4 in-app purchases, starting at $2.99 per month. Reef Book asks for nothing beyond the download.

Reef Book ships an update every 6 months, Reef Diary Aquarium Management monthly. Both last shipped on October 30, 2026.

## The numbers

| Metric | Reef Book | Reef Diary Aquarium Management |
| --- | --- | --- |
| Price | $5.99 | **Free** |
| Rating | — | **[1.0 (1 ratings)](https://appshunter.io/ios/app/reef-diary-aquarium-management/id6746352304/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 6 months | **Monthly** |
| Monetization | — | Freemium |
| Size | 166 MB | 58 MB |
| Requires iOS | 26.0 | **15.1** |
| Devices | iPhone, iPad, Mac | **iPhone, iPad, iPod, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [ReefSoft LLC](https://appshunter.io/developer/1789068807) | [Christian Buchholz](https://appshunter.io/developer/1816370032) |

## What reviewers say

### Reef Book

[App page](https://appshunter.io/ios/app/reef-book/id6740756140)

**Features:** iMessage stickers

**In-app purchases:** none


### Reef Diary Aquarium Management

[App page](https://appshunter.io/ios/app/reef-diary-aquarium-management/id6746352304)

Manage your reef or freshwater aquarium with this comprehensive tool. Track water parameters, schedule maintenance, and monitor your aquatic life and equipment. Works offline to keep your ecosystem healthy and thriving.

**Highlights:** Smart parameter tracking for reef and freshwater, Visual trend charts for water parameters, Multiple tank support, Equipment and livestock inventory, Maintenance task scheduler with reminders, Offline functionality

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Reef Diary - Monthly | $2.99 | per month |
| Reef Diary - Yearly | $24.99 | per year |
| Enterprise Monthly Subscription | $89.99 | per month |
| ReefDiary Yearly Enterprise | $699.00 | per year |


## Frequently asked questions

### Is Reef Book free?

Reef Book costs $5.99, with no in-app purchases.

### Is Reef Diary Aquarium Management free?

Reef Diary Aquarium Management is free to download, with in-app purchases available.

### Do Reef Book or Reef Diary Aquarium Management have ads?

Neither Reef Book nor Reef Diary Aquarium Management shows ads.

### Which is updated more often, Reef Book or Reef Diary Aquarium Management?

Reef Book ships an update every 6 months, and Reef Diary Aquarium Management monthly. Most recently, Reef Book was updated on October 30, 2026 and Reef Diary Aquarium Management on October 30, 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.*