# AquaCalculator vs Reefability

The clearest difference is rating: AquaCalculator at 3.7 against Reefability's 2.9. AquaCalculator also leads on review sentiment (67% vs 27%). Reefability's advantage is monetization model (free with in-app purchases vs subscription) and update cadence (every 4 days vs monthly). On price, ratings volume, ads and in-app purchases there is nothing between them.

Both are free to download. AquaCalculator sells 5 in-app purchases, starting at $3.99 per month and Reefability sells 2 in-app purchases, starting at $5.99 per month. Whichever you choose, the download price is not the number that matters.

AquaCalculator holds the better App Store score, 3.7 against 2.9. Both are backed by a comparable volume of ratings — 12 and 29 respectively. Written reviews point the same way: 67% of AquaCalculator's written reviews are positive against 27% of Reefability's.

AquaCalculator ships an update monthly, Reefability every 4 days. The most recent releases landed on September 21, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | AquaCalculator | Reefability |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.7 (12 ratings)](https://appshunter.io/ios/app/aquacalculator/id1449511522/reviews)** | [2.9 (29 ratings)](https://appshunter.io/ios/app/reefability/id6636472070/reviews) |
| Number of ratings | 12 | **29** |
| Positive reviews | **66.7% of reviews** | 26.9% of reviews |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Monthly | **Every 4 days** |
| Monetization | Subscription | **Free with in-app purchases** |
| Size | 49 MB | 70 MB |
| Requires iOS | 18.6 | **15.0.0** |
| Devices | **iPhone, iPad, Mac, Vision Pro** | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Thallos](https://appshunter.io/developer/544488594) | [Reefability](https://appshunter.io/developer/1762764786) |

## What reviewers say

### AquaCalculator

[App page](https://appshunter.io/ios/app/aquacalculator/id1449511522)

This app helps dedicated marine aquarists manage and document their aquariums. It tracks water parameters, manages animal stock, and calculates precise salt and nutrient additions. It also offers tools for adjusting calcium, alkalinity, and magnesium levels.

**Highlights:** Manage multiple aquariums, Water value documentation with graphs and tables, Animal administration with notes and pictures, Recurrent memory for care tasks, Salt quantity estimation, Nutrient and chemical adjustment calculators, Extensive setting options

**Features:** Family Sharing

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| AquaCalculator monthly | $3.99 | per month |
| AquaCalculator yearly | $19.99 | per year |
| A large coffee | $3.99 | one-time |
| Ice Tead and a Sandwich | $9.99 | one-time |
| Something to learn | $39.99 | one-time |


### Reefability

[App page](https://appshunter.io/ios/app/reefability/id6636472070)

This AI-powered app offers scientific precision for managing coral reef aquariums. It analyzes microbiome health, water chemistry, and light optimization, and can identify issues from tank photos. It provides tools for hobbyists and professionals to maintain thriving reef ecosystems.

**Highlights:** AI-driven analysis of reef tank health, Smart photo diagnostics for issue identification, Evidence-based solutions and recommendations, Ecosystem stability insights, Professional tools for reef stores and professionals, Integrated parameter monitoring

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1-Month | $5.99 | per month |
| 12-Month | $24.99 | per year |


## Frequently asked questions

### Is AquaCalculator free?

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

### Is Reefability free?

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

### Which has better reviews, AquaCalculator or Reefability?

AquaCalculator is rated higher. AquaCalculator averages 3.7 out of 5 from 12 ratings, while Reefability averages 2.9 from 29 ratings.

### Do AquaCalculator or Reefability have ads?

Neither AquaCalculator nor Reefability shows ads.

### Which is updated more often, AquaCalculator or Reefability?

AquaCalculator ships an update monthly, and Reefability every 4 days. Most recently, AquaCalculator was updated on September 21, 2026 and Reefability on September 23, 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.*