# ReefDoser vs HYDROS App

The clearest difference is rating: HYDROS App at 3.7 against ReefDoser's 1.0. HYDROS App also leads on ratings volume (22 vs 1) and review sentiment (62% vs 54%). ReefDoser's advantage is iOS requirement (10.0 vs 15.6). On price, update cadence, ads and in-app purchases there is nothing between them.

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

HYDROS App holds the better App Store score, 3.7 against 1.0. That said, the two scores are not equally well evidenced: HYDROS App has 22 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 54% of ReefDoser's written reviews are positive against 62% of HYDROS App's.

Both ship on a similar rhythm, roughly every 3 months. The most recent releases landed on October 9, 2026 and October 18, 2026 respectively.

## The numbers

| Metric | ReefDoser | HYDROS App |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/reefdoser/id353011315/reviews) | **[3.7 (22 ratings)](https://appshunter.io/ios/app/hydros-app/id1455344294/reviews)** |
| Number of ratings | 1 | **22** |
| Positive reviews | 54.2% of reviews | **62.3% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | Every 3 months |
| Monetization | Free | Free |
| Size | 23 MB | 70 MB |
| Requires iOS | **10.0** | 15.6 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Pixelwand Ltd](https://appshunter.io/developer/353011318) | [Coralvue](https://appshunter.io/developer/1455344293) |

## What reviewers say

### ReefDoser

[App page](https://appshunter.io/ios/app/reefdoser/id353011315)

This app helps tropical marine aquarium owners calculate precise dosages for essential elements like Calcium, Magnesium, and Alkalinity. It features an extensive database of over 70 products to ensure optimal water parameters for your reef tank.

**Highlights:** Element dosage calculation, Calcium, Magnesium, Alkalinity tracking, Potassium, Iodine, Strontium, Boron, Silicate, Product database (70+ items), Tropical marine aquarium focus

**Features:** macOS Compatibility

**In-app purchases:** none


### HYDROS App

[App page](https://appshunter.io/ios/app/hydros-app/id1455344294)

Easily monitor and control your aquarium's vital parameters like temperature, pH, and salinity. Manage all your connected devices, including ATOs, lights, and pumps, with a user-friendly interface. Quick setup with preset configurations means no coding is required to get your system running.

**Highlights:** Monitor temperature, ORP, pH, salinity, Control ATO, lights, heaters, pumps, User-friendly interface, Quick setup with presets, Manage multiple devices and aquariums, Set schedules and create modes

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

**In-app purchases:** none


## Frequently asked questions

### Is ReefDoser free?

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

### Is HYDROS App free?

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

### Which has better reviews, ReefDoser or HYDROS App?

HYDROS App is rated higher. ReefDoser averages 1.0 out of 5 from 1 ratings, while HYDROS App averages 3.7 from 22 ratings.

### Do ReefDoser or HYDROS App have ads?

Neither ReefDoser nor HYDROS App shows ads.

### Which is updated more often, ReefDoser or HYDROS App?

ReefDoser ships an update every 3 months, and HYDROS App every 3 months. Most recently, ReefDoser was updated on October 9, 2026 and HYDROS App on October 18, 2026.

---

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