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Nature Dimensions

N-Fill Smart Auto Top Off System

In stock
Out of stock
SKU
257012
Rating:
96% of 100
1  Review Add Your Review
$69.99 $69.99

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Risk Free 365 Returns

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365 Day Risk Free Returns

No longer need what you ordered? Ordered one too many? We've got your back.


Return new, unopened products in original packaging within 365 days for a full refund.

Under 60 days? No problem. We’ll issue your refund to the original form of payment. Over 60 days? Still no problem. We'll issue your refund in the form of store credit, which you can use like cash on our website.


Return unused, open box products within 30 days.

Open box but still unused? We can help. We’ll issue your refund to the original form of payment minus a small 10% restocking and handling fee.

Some exclusions apply, for more information go to Return & Replacement Details.

Details

Affordable & Reliable Auto Top Off System

  • Redundant, Dual Float Sensors
  • Smart Over-Fill Protection Built-In
  • Intuitive Controller w/ Status Indicator LEDs
  • Ideal for Nano to Mid-Size Tanks
  • Safe for Freshwater or Saltwater Aquariums

 

The N-Fill Auto Top Off (ATO) is a simple, affordable system built specifically for nano to mid-size aquariums. As water evaporates, the N-Fill automatically replaces it with fresh water, keeping your tank’s water level stable day after day. This helps protect equipment like heaters and filters from running partially dry, maintains consistent water conditions for fish and plants, and eliminates the need for manual top-offs. Dual float sensors and smart overfill protection add peace of mind, while the compact controller, clear status LEDs, and easy setup make it an all around great choice.

Dual Float Sensors

Two independent float switches monitor the same water line. The controller starts a refill whenever either sensor detects low water. Even if one sensor fails, the other still triggers top-offs. This redundancy helps prevent missed refills and provides an extra layer of stability compared to most ATOs on the market.

Smart Overfill Protection

If the pump runs for more than about 90 seconds, the controller pauses filling and triggers an audible alarm with a red status LED. This fail-safe helps prevent overfilling if a float sticks low, flow is restricted, or the reservoir behaves unexpectedly.

Simple On-Board Control Buttons

  • Manual: Hold to run the pump for priming or quick refills, release to stop.
  • Pause: Press once for a 30-minute pause. Ideal for feeding or light maintenance.
  • Stop: Press once to disable automatic filling during major maintenance. Resumes after 24 hours.

LED Status Indicators

  • Power: Controller has power and is ready.
  • Filling: ATO pump is actively running.
  • Status: Off during normal operation, blinking when paused, and solid red during stop mode or overfill alarm

 

Specifications

  • Power Input: AC 100–240 V, 50/60 Hz
  • Power Output: DC 12V 1A, UL Listed Adapter
  • Maximum Pump Head: 160 cm | 63"
  • Maximum Flow Rate: 180 L/h | 47.6 GPH
  • Maximum Glass Thickness: Up to 15 mm | 0.6"
  • Sensor Adjustment Range: Up to 10 cm | 4" Below Tank Rim
  • Tank Compatibility: Freshwater and Saltwater Aquariums
  • Control Modes: Manual Fill, 30-Minute Pause, 24-Hour Stop
  • Over-Fill Protection: Auto Timeout After ~90 Seconds with Alarm and Status LED
  • LED Indicators: Power, Filling, Status

What's Included?

N-Fill Controller

Dual Float Sensors with Adjustable Holder

N-Neon ATO Tubing Organizer

Submersible DC Pump

Water Tubing (2 M | 6.5 ft)

Siphon Breaker Connector with Cover

UL Listed 12V 1A Power Adapter

More Information
More Information
SKU 257012
UPC 5065025142048
Aquarium Type Saltwater, Freshwater
Max Tank Thickness 15mm / 0.59in. (≈19/32")
Included Mounting Hang On/Bracket
Control Type Onboard Controls
Pump Included Yes
Pump Rotor Type Impeller
Flow Rate Up to 180 l/h | 47.6 GPH
Tubing Length 2 m | 6.5 ft
Warranty 1 Year Manufacturer Warranty
Water Level Detection Float Valve or Switch
Safety Features Overflow Timer, Includes Anti-Siphon Valve
Max Head Height Under 5 Feet
Reviews 4
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