---
product_id: 550266203
title: "Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue"
brand: "useek"
price: "€ 67.78"
currency: EUR
in_stock: true
reviews_count: 13
category: "Useek"
url: https://www.desertcart.it/products/550266203-auto-top-off-for-saltwater-aquarium-water-ato-system-both
store_origin: IT
region: Italy
---

# Nano 0.7in sensor size Ultra-quiet pump operation QST real-time refill monitoring Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue

**Brand:** useek
**Price:** € 67.78
**Availability:** ✅ In Stock

## Summary

> 💧 Keep your tank flawless, your fish happy, and your weekends worry-free!

## Quick Answers

- **What is this?** Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue by useek
- **How much does it cost?** € 67.78 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.it](https://www.desertcart.it/products/550266203-auto-top-off-for-saltwater-aquarium-water-ato-system-both)

## Best For

- useek enthusiasts

## Why This Product

- Trusted useek brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Plug & Play Installation:** Complete kit with everything you need for a quick 15-20 minute setup—perfect for busy pros who want hassle-free aquarium care.
- • **Discreet Nano-Sensor Design:** At just 0.7 inches, the compact sensor blends seamlessly into any rimmed or rimless aquarium without disrupting your sleek setup.
- • **Reliable Support & Warranty:** Backed by a two-year warranty and responsive customer service, ensuring your investment is protected and your aquatic ecosystem thrives.
- • **Effortless Water Level Stability:** Automatically maintains perfect salinity by topping off evaporated water, so your reef or fresh tank stays balanced 24/7.
- • **Smart Safety with QST Technology:** Advanced refill time calculation halts the pump if anomalies occur, preventing overflows, dry runs, and sensor errors—peace of mind guaranteed.

## Overview

The Useek Auto Top Off (ATO) system is a compact, ultra-quiet water level controller designed for both saltwater reef and freshwater aquariums. Featuring a tiny 0.7-inch sensor and smart QST technology, it automatically maintains stable water levels to prevent salinity fluctuations and protect aquatic life. Easy to install with a complete kit, it offers real-time safety alerts and pump shutoff to avoid overfilling or dry running. Supported by a two-year warranty and dedicated customer service, this ATO system is a must-have for aquarium enthusiasts seeking reliable, hands-off maintenance.

## Description

desertcart.com : Useek Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue : Pet Supplies

Review: Should have purchased sooner - I've had this saltwater tank for awhile and I should have purchased this auto top off so much sooner. This unit really has made maintaining my fish tank so much easier. The size of this is less than an inch and it doesn't stick out in my tank either. It fit perfectly on the rimless setup without taking up a lot of space. Setup was super easy and everything I needed to get this running came in the box. Overall, it took me about 15-20 to have this setup and ready to use. I really like the safety feature it has that monitors and refills my tank with an auto shut off. I have left my house for the weekend and came back to absolutely no mess but my tank maintained its level of water. Plus, once its attached to my tank, it doesn't fall off either, very sturdy. Plus the other thing I noticed is that this whole thing doesn't make any noise. All I hear is running water every now and then and that's it. There have been no sudden swings of stressing my fish out either.
Review: Great ATO for the price😊 - I would like to start of buy saying I have been in the aquarium hobbies for over a decade and had always taken steps to reduce evaporation as much as reasonably possible. However after many years of topping off my tanks manually I decided to look in to an ATO, after reading many reviews and seeing a few videos I settled on this one and I'm glad I did. The ATO is very simple to to set up in just a few minutes. The sensor that goes inside of your aquarium is very small and the magnet used to secure it in place feels adequately strong enough that I'm not worried about it falling inside of my aquarium. I purchased a smallish 7 gallon water container one would use for camping to use as a reservoir for hold additional water and the small pump head fits very nicely inside. So far it has been working great. There is very and I mean very little noise heard from the pump when it kicks into action and the only time I've heard it was when everything in the room is shut off and its stone silent in the room. The only draw back that I can think that may throw some people off is the sensor it's self is a very very bright night light so best not to use in a bedroom I'd say if you like the dark that is but seeing as the aquariums in question are located in my home office / game room it doesn't bother my in the least. I have plugged my ATO into a smart plug to make water changes and gravel vacuuming easier as I can disable it while doing so. Hopefully people find this review helpful. 😊

## Features

- WHY YOU NEED ATO? - All Aquarium regularly evaporate water. In salt water Aquarium, as the water evaporates, the water level in Aquarium will drop and the salinity concentration will rise. Compared with other methods,The ATO system automatically maintains the water level in the aquarium, preventing fluctuations in salinity concentration and maintaining a stable and healthy environment for aquatic life.
- SPACE-SAVING, COMPACT DESIGN - With a nano size of only 0.7 inches diameter, this Auto Top Off for aquariums is both unobtrusive and elegant, fitting seamlessly in rimmed or rimless tanks and sumps.
- REAL-TIME PROTECTION WITH QST - Our ATO system carefully calculates and adjusts to the ideal fill time, offering visual alerts and stopping the pump if it detects a refilling time 6 times longer than expected, ensuring protection against overfilling, dry running, and sensor malfunctions.
- EASY INSTALLATION & VERSATILE USE - The Auto Top Off kit includes everything you need for a hassle-free setup, making it simple to integrate into any rimmed or rimless aquarium. A perfect gift for aquarium enthusiasts, this system is a delightful surprise for friends and family alike.
- TWO-YEAR WARRANTY & RESPONSIVE CUSTOMER SERVICE - Your satisfaction is our priority, so we offer a two-year product warranty and friendly customer support to address any questions or concerns. Enjoy peace of mind with our free replacement policy and helpful assistance.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0CFVWDKMC |
| ASIN  | B0CFVWDKMC |
| Best Sellers Rank | #8,208 in Pet Supplies ( See Top 100 in Pet Supplies ) #11 in Aquarium Water Pumps |
| Brand Name | Useek |
| Color | Blue |
| Customer Reviews | 4.0 4.0 out of 5 stars (581) |
| Date First Available | May 15, 2023 |
| Date First Available  | May 15, 2023 |
| Included Components | Pump |
| Item Package Dimensions L x W x H | 6.46 x 6.34 x 2.68 inches |
| Item Weight | 0.4 Kilograms |
| Item model number | AT-200 |
| Item model number  | AT-200 |
| Manufacturer | Useek |
| Manufacturer  | Useek |
| Material | Acrylonitrile Butadiene Styrene (ABS) |
| Model Name | Blue-1 |
| Package Dimensions  | 6.46 x 6.34 x 2.68 inches; 14.07 ounces |
| Style | Modern |
| Target Audience Keyword | fish |
| Warranty Description | 1 |

## Product Details

- **Brand:** Useek
- **Color:** Blue
- **Included Components:** Pump
- **Item Weight:** 0.4 Kilograms
- **Material:** Acrylonitrile Butadiene Styrene (ABS)
- **Shape:** Irregular shape
- **Special Feature:** Space-Saving, Real-Time Protected, Automatic Water Level Maintenance
- **Style:** Modern
- **UPC:** 799355749961
- **Vivarium Type:** Aquarium

## Images

![Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue - Image 1](https://m.media-amazon.com/images/I/713hjxk8HnL.jpg)

## Questions & Answers

**Q: Would this work on a 60 gallon AIO? I’ve only had it on a nano**
A: More surface area = longer top off

**Q: Does the sensor light up or is there no light in the sensor?**
A: It lights up.  It blinks when topping off

## Customer Reviews

### ⭐⭐⭐⭐⭐ Should have purchased sooner
*by R***A on September 23, 2025*

I've had this saltwater tank for awhile and I should have purchased this auto top off so much sooner. This unit really has made maintaining my fish tank so much easier. The size of this is less than an inch and it doesn't stick out in my tank either. It fit perfectly on the rimless setup without taking up a lot of space. Setup was super easy and everything I needed to get this running came in the box. Overall, it took me about 15-20 to have this setup and ready to use. I really like the safety feature it has that monitors and refills my tank with an auto shut off. I have left my house for the weekend and came back to absolutely no mess but my tank maintained its level of water. Plus, once its attached to my tank, it doesn't fall off either, very sturdy. Plus the other thing I noticed is that this whole thing doesn't make any noise. All I hear is running water every now and then and that's it. There have been no sudden swings of stressing my fish out either.

### ⭐⭐⭐⭐⭐ Great ATO for the price😊
*by S***N on March 13, 2024*

I would like to start of buy saying I have been in the aquarium hobbies for over a decade and had always taken steps to reduce evaporation as much as reasonably possible. However after many years of topping off my tanks manually I decided to look in to an ATO, after reading many reviews and seeing a few videos I settled on this one and I'm glad I did. The ATO is very simple to to set up in just a few minutes. The sensor that goes inside of your aquarium is very small and the magnet used to secure it in place feels adequately strong enough that I'm not worried about it falling inside of my aquarium. I purchased a smallish 7 gallon water container one would use for camping to use as a reservoir for hold additional water and the small pump head fits very nicely inside. So far it has been working great. There is very and I mean very little noise heard from the pump when it kicks into action and the only time I've heard it was when everything in the room is shut off and its stone silent in the room. The only draw back that I can think that may throw some people off is the sensor it's self is a very very bright night light so best not to use in a bedroom I'd say if you like the dark that is but seeing as the aquariums in question are located in my home office / game room it doesn't bother my in the least. I have plugged my ATO into a smart plug to make water changes and gravel vacuuming easier as I can disable it while doing so. Hopefully people find this review helpful. 😊

### ⭐ Buyer beware! Designed to break. Low grade disposable product.
*by A***R on February 10, 2025*

I've now purchased 3 times. All 3 of these are absolutely garbage. They work for ruffly 1 to 6 months and then ultimately fail. Reviews say it's great, but notice none of the reviews mention "Years of use". Longevity wise, this gets 1 out of 10. Waste of money. The pump is a 2 out of 10. It's slow, small and breaks easily. It's the kind of pump you'd expect to pay about $1 for. The sensors are NOT water proof and in fact the sensors will take in water and then create a film inside that destroys the sensor. All in all, this is an epic waste of money. Amazon should be ashamed to sell this product, as it's designed to break and you will need to replace it again and again and again. Quite frankly, I'd like my cash back. This is a scam product in which I have 3 of. 3 is enough to prove a point. If the seller or anyone at Amazon would care to interject, maybe we could establish some accountability. For this product, there is none. Buyer beware. This is a disposable product with a shirt lifespan. Absolutely rubbish.

## Frequently Bought Together

- Useek Auto Top Off for Saltwater Aquarium Water ATO System for Both Reef and Fresh Tank - Blue
- Aquatic Life RO Buddie 4-Stage Reverse Osmosis Deionization Water Filter System RO/DI Filtration Units for Aquarium, 50 GPD

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*Product available on Desertcart Italy*
*Store origin: IT*
*Last updated: 2026-01-28*