Aquamedic Refill System 2.0

Aqua Medic Refill System 2.0 – ATO — Three-sensor automatic top-up with overfill cut-out and reservoir alarm

Evaporation takes several litres a day from a warm reef sump, and every litre lost raises the salinity of what is left. Aqua Medic Refill System 2.0 – ATO (SKU: AM50277) is Aqua Medic’s automatic top-up system for aquariums and cabinet filters, replacing evaporated water from a separate reservoir so the level and salinity stay constant. It uses three float switches rather than one: N1 sets the working level, N2 sits above it as a safety cut-out if N1 sticks, and N3 sits in the reservoir to protect the refill pump from running dry. Everything runs at 12 V low voltage from a 100–240 V power supply, with plug connections on every cable for easy installation and servicing.

N1 has a delay function, so ripples and surface movement do not set the pump switching on and off. If N1 fails and the water rises to N2, refilling is interrupted, which Aqua Medic describes as a safety shutdown for a defective level sensor. When the reservoir runs low, N3 stops the pump and triggers an optical and acoustic alarm. Status lights on the controller show refilling in progress, low reservoir water with an audible beep, and power on. The supplied refill pump draws 0.5 to 5.0 W at 3.5 to 12 V DC and delivers up to 350 L/h with a maximum head of 220 cm, feeding through 2 m of 8/12 mm hose. The supplied N1 and N2 holder needs about 13 cm at the aquarium or sump rim, and both sensors sit above the water line with their floats pointing upward.

Usage & Application

When to Use

• Reef aquariums: Keeping salinity steady by replacing evaporation with fresh RO water.
• Sump systems: Holding a constant level in the return section so the pump never runs low.
• Holidays and busy weeks: Top-up continues without daily attention.
• Open-top tanks: Higher evaporation that would otherwise mean daily hand-filling.

Installation & Setup Guide

• Cables first: Connect every sensor and the pump before switching on the power supply.
• Fit N1 and N2: Mount them on the supplied holder at the desired level and safety level, floats upward.
• Set the reservoir: Stick the pump and N3 to the bottom with the suction cups, and keep the reservoir no higher than the hose outlet.
• Route the hose: Fix the outlet above the water so no siphon can form; keep sensors free of algae.

Product Specifications & Highlights

Key Features

• Three float switches: Working level, overfill cut-out and reservoir low-level.
• Delay switching: Ignores surface movement for steady operation.
• Dry-run protection: Stops the pump and sounds an alarm when the reservoir is low.
• 12 V low voltage: Safe voltage at the tank and in the reservoir.
• Plug-in cables: Every component connects and disconnects without tools.

Product Details

• Brand: Aqua Medic (Germany)
• SKU: AM50277
• Barcode (GTIN/EAN): 4025901141702
• Product Type: ATO Systems > Automatic Top-Up System
• Refill Pump: 3.5–12 V DC, 0.5–5.0 W; max. 350 L/h, max. head 220 cm
• Power Supply: 100–240 V AC, 50/60 Hz input; 12 V DC output
• Sensors: 3 float switches (level, safety, reservoir)
• Hose: 2 m, 8/12 mm
• In the Box: Power supply, controller, 3 float switches, refill pump, 2 m refill hose
• Sensor Holder: Needs approx. 13 cm at the rim
• Warranty: 24 months via the dealer
• Target Environment: Marine and freshwater aquariums with sumps