---
product_id: 550266203
title: "Auto Top Off System Saltwater Aquarium, Water ATO for Reef Fresh Tank | Stable Water Levels & Salinity, QST Real-Time Anti-Overflow, 1mm Precision Sensing, Easy Setup, 2-Year Warranty, Blue"
brand: "useek"
price: "¥13874"
currency: JPY
in_stock: true
category: "Useek"
url: https://www.desertcart.jp/products/550266203-auto-top-off-system-saltwater-aquarium-water-ato-for-reef
store_origin: JP
region: Japan
---

# 0.7-inch nano compact design Easy installation kit included Real-time QST protection with auto shutoff Auto Top Off System Saltwater Aquarium, Water ATO for Reef Fresh Tank | Stable Water Levels & Salinity, QST Real-Time Anti-Overflow, 1mm Precision Sensing, Easy Setup, 2-Year Warranty, Blue

**Brand:** useek
**Price:** ¥13874
**Availability:** ✅ In Stock

## Summary

> 💦 Keep your reef flawless with smart, silent water top-offs!

## Quick Answers

- **What is this?** Auto Top Off System Saltwater Aquarium, Water ATO for Reef Fresh Tank | Stable Water Levels & Salinity, QST Real-Time Anti-Overflow, 1mm Precision Sensing, Easy Setup, 2-Year Warranty, Blue by useek
- **How much does it cost?** ¥13874 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/550266203-auto-top-off-system-saltwater-aquarium-water-ato-for-reef)

## 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 Setup:** Complete kit for hassle-free installation in rimmed or rimless tanks
- • **Salinity Stability:** Maintains perfect water level to keep salt concentration balanced
- • **Nano-Sized Elegance:** Sleek 0.7-inch diameter fits any tank discreetly
- • **Smart QST Protection:** Auto stops pump if refill time exceeds 6x expected, preventing overflows
- • **Peace of Mind Warranty:** Two-year coverage with responsive customer support

## Overview

The Useek Auto Top Off (ATO) system is a compact, intelligent pump designed to maintain stable water levels in both saltwater and freshwater aquariums. Its nano-sized design fits seamlessly in any tank setup, while real-time QST technology prevents overfilling and pump damage by monitoring refill times. Easy to install and backed by a two-year warranty, this system ensures consistent salinity and a healthy aquatic environment, making it a must-have for serious aquarium enthusiasts.

## Description

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

## 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 |
| Additional Features | Space-Saving, Real-Time Protected, Automatic Water Level Maintenance |
| Best Sellers Rank | #10,500 in Pet Supplies ( See Top 100 in Pet Supplies ) #23 in Aquarium Water Pumps #77 in Aquarium Water Treatments |
| Brand Name | Useek |
| Color | Blue |
| Customer Reviews | 3.9 3.9 out of 5 stars (767) |
| Date First Available  | May 15, 2023 |
| Included Components | Pump |
| Item Shape | Irregular shape |
| Item Type Name | Pump |
| Item Weight | 0.4 Kilograms |
| Item model number  | AT-200 |
| Manufacturer | Useek |
| Manufacturer  | Useek |
| Manufacturer Part Number | AT-200 |
| Material Type | Acrylonitrile Butadiene Styrene (ABS) |
| Model Number | AT-200 |
| Package Dimensions  | 6.46 x 6.34 x 2.68 inches; 14.07 ounces |
| Product Style | Modern |
| Specific Uses For Product | Reef and Freshwater Aquariums |
| Target Species | Fish |
| UPC | 799355749961 |
| Unit Count | 1.00 Count |
| Vivarium Type | Aquarium |
| 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
- **Specific Uses For Product:** Reef and Freshwater Aquariums
- **Style:** Modern
- **UPC:** 799355749961

## Images

![Auto Top Off System Saltwater Aquarium, Water ATO for Reef Fresh Tank | Stable Water Levels & Salinity, QST Real-Time Anti-Overflow, 1mm Precision Sensing, Easy Setup, 2-Year Warranty, Blue - Image 1](https://m.media-amazon.com/images/I/713hjxk8HnL.jpg)

## Available Options

This product comes in different **Color** options.

## 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

## 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

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.jp/products/550266203-auto-top-off-system-saltwater-aquarium-water-ato-for-reef](https://www.desertcart.jp/products/550266203-auto-top-off-system-saltwater-aquarium-water-ato-for-reef)

---

*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-08-05*