# AquaCalculator vs Reefmaster Piper

The clearest difference is in-app purchases: Reefmaster Piper at none against AquaCalculator's 5. Reefmaster Piper also leads on iOS requirement (15.0 vs 18.6). AquaCalculator's advantage is device support (4 vs 2). On price, update cadence and ads there is nothing between them.

Both are free to download. AquaCalculator sells 5 in-app purchases, starting at $3.99 per month. Reefmaster Piper asks for nothing beyond the download.

AquaCalculator ships an update every 3 weeks, Reefmaster Piper monthly. The most recent releases landed on October 26, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | AquaCalculator | Reefmaster Piper |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.7 (12 ratings)](https://appshunter.io/ios/app/aquacalculator/id1449511522/reviews)** | — |
| Number of ratings | **12** | — |
| Positive reviews | 66.7% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Monthly |
| Monetization | Subscription | — |
| Size | 49 MB | 115 MB |
| Requires iOS | 18.6 | **15.0** |
| Devices | **iPhone, iPad, Mac, Vision Pro** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Thallos](https://appshunter.io/developer/544488594) | [Reefmaster](https://appshunter.io/developer/1569183159) |

## 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 |


### Reefmaster Piper

[App page](https://appshunter.io/ios/app/reefmaster-piper/id6741764293)

**In-app purchases:** none


## Frequently asked questions

### Is AquaCalculator free?

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

### Is Reefmaster Piper free?

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

### Do AquaCalculator or Reefmaster Piper have ads?

Neither AquaCalculator nor Reefmaster Piper shows ads.

### Which is updated more often, AquaCalculator or Reefmaster Piper?

AquaCalculator ships an update every 3 weeks, and Reefmaster Piper monthly. Most recently, AquaCalculator was updated on October 26, 2026 and Reefmaster Piper on October 8, 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.*