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Auto Top Off

Auto Top Off

85 reviews
$ 99.99

Finally, a top-off control sensor that is mounted to your sump with a magnet rather than a clunky bracket!  Driven by a pressure-sensitive switch located in the relay box, a strong magnetic field won't affect its operation.  The sensor tube can't get clogged with calcium deposits or activated by wayward snails as there are no moving parts.  Our top-off system is capable of maintaining the sump water level within +/- 1/4" tolerance (1/2" overall) and features a built-in range buffer or hysteresis effect, which prevents rapid on-off switching that sometimes occurs when cheap float switches bob up and down in small waves.  The magnet bracket is capable of holding on up to 1/2" thick glass.  The slim design relay box is unobtrusive and can handle up to a 3 amp pump at 110v AC.  The green LED light indicates when the circuit is active and the pump is running.

The magnetic bracket also contains both an adjustable 1/4" to 1/2" fitting, useful for holding the tube from your top-off pump in place.  This fitting can be switched out for an optional backup mechanical float valve, which will physically close and stop the flow from your pump in the event of an electrical or switch issue.  

Our digital output version is now available for use with most aquarium controllers.  This version is designed without an outlet; just plug the ATO pump into your controller's relay box and set up the controller to read the pressure switch state (see instruction manual for details).  It is available with the plug types of several popular aquarium controllers.  For example, Neptune Apex uses a "minidin-8" style plug.  To use this, simply plug into the port marked "I/O" on the controller, and program according to instructions.  If you already have something plugged in to that port, you will want to use their Breakout Box and select the "bare wire" option below.  See instruction manual for further details. Bare wire connection is 2 strand, non-polarized 22 AWG shielded wire. In the case of ReefKeeper Lite/Elite, use this option with the float switch adapter wire that came with your controller and/or SW5 Switch Module.

Cerebra, Reef Angel, and RKL/RKE compatible plugs are also available.
 
The Digital Output version allows several non-standard uses for this switch. For example, it can be a low level sensor in your sump that is impervious to coralline algae and snails, can turn off your return pump and send you a text message at the same time. There are a lot of options since you can reverse the logic of the switch at the controller.

Our switch and all components are made in the USA. 


Technical Data:

Water level sensitivity: 1/2" 
Magnet strength: up to 1/2" glass
Magnet bracket dimensions: 1-3/4" front to back x 2-1/4" wide (excluding external magnet half, 1/2" thick)
Switch box dimensions: 4" x 2.25" 
Input power: AC 110v
Relay box capacity: 3 amps
Switch rating: 10+ million cycles
Warranty: 1 year

Click here for Standard outlet box ATO installation manual
Click here for Digital output ATO installation manual

Click here for ATO and related Pressure Switch troubleshooting guide

Customer Reviews
4.9 Based on 85 Reviews
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Filter Reviews:
PM
01/19/2021
Paige M.
United States United States
Reliable auto top off

Installation was somewhat difficult because the instructions were sketchy and my unfamiliarity with Apex system. But it has been reliable ever since.

RP
12/25/2020
Roshan P.
United States United States
Didn't include pressure sensor in package

Had to wait about 2 extra weeks to get my ATO setup since they didn't include a pressure sensor in the package. Quality otherwise seems good.

TT
12/22/2020
Timothy T.
United States United States
Peace of Mind ATO

I was shopping for an ATO for my new setup. I read a lot of reviews and complaints about malfunctioning eyes and ATO's dumping all their water into the sump. I wanted something safe with a backup. I inherited an Avast standard ac outlet switch for my bottle that holds the skimmate and instantly fell in love with it, works flawlessly. Such a unique concept for a switch and with the optional float valve, i am sure this thing will never flood my sump. it was easy to set up and connect to my Apex. i love the little pump too! 1 week of use, and so far, its been great. only complaint i have is the magnet seems a little weak for my sump. i wish it was stronger.

JH
12/07/2020
James H.
United States United States
Best Level sensing product made

I've used every level sensor on the market. The optical ones get cloudy over time causing them to give false readings, the electric floats jam up sometimes, the mechanical valves can stick or get gummed up by Kalk, the Pressure based level sensor you sell is the only one that has been reliable in the long haul. I still have other types as backups, but since I bought my first one years ago I haven't needed the backup.

LS
09/10/2020
Louis S.
United States United States
Best ATO

Avast Marine’s auto top off is flawless. Construction is excellent, of course being made in the United States. It was effortless setting up with the GHL!