More robust power supply
A sturdier power supply built for years of around-the-clock use.
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A complete auto top-off kit that's reliable, easy to set up, and clean looking in just about any reef system. Everything you need to start maintaining your water level automatically is in the box.

We keep improving our products even after release, so the current version of the ATO includes refinements you won't find in earlier units. The pump and power supply have proven to be extremely reliable, and these updates build on that.
A sturdier power supply built for years of around-the-clock use.
Extra cable length gives you more freedom to place the pump where it works best.
A slightly larger motor further improves motor lifespan and reliability.

Both halves of the magnetic mount are fully submersible, so the outer magnet can sit underwater too. Mount it on a sump baffle or any panel with water on both sides.
The infrared sensor is only 0.86" (22 mm) long, so it's far less noticeable in your tank and adds less water with each top-off.
Works on glass and acrylic, and holds securely on panels up to 5/8" (16 mm) thick.
All major components are finished in deep black, with black tubing to match, so they blend into most sumps and displays.
Fits tank trims or euro braces up to 0.6" (15 mm) thick and keeps the outlet exactly where you want it.
The pump and power supply have proven to be extremely reliable, running around the clock in reef systems day after day.
A conductivity sensor on the pump side detects when your reservoir is empty and shuts the pump off automatically to prevent damage.
Refined seals on the sensor and magnet housing give better protection and a longer service life than our previous Prism ATO.
IP65-rated plugs on both the power supply and pump add an extra layer of safety and durability.
Runs more quietly than our earlier Prism ATO pump, so you'll barely notice it working.
The pump and power supply each run to a Y-cable, which connects to the sensor. Here's how far each cable goes.
Siphon break placement: The included siphon break lets air into the line when the pump is off, which stops unwanted siphoning. It can also let out a small amount of water, so always position it inside the rim of your aquarium, sump, or ATO reservoir.
Add 36 or 48 month extended coverage for extra peace of mind. Want an even cleaner install? Our Elite Magnet Mount adds an integrated tubing holder.