Need Help? Call us at 1-317-895-9005
or email us at

Proudly serving Aquarists since 1996

IceCap ATO EZ Automatic Top-off System

Item #
Ice Probe
Eligible for Free Shipping Program
Out Of Stock


The IceCap ATO EZ is a reliable triple optical sensor Auto Top Off management system that monitors and automates refilling evaporated water. Includes everything needed to install and operate.
Replenish Evaporated Water... with Confidence!
The IceCap ATO EZ System is an easy-to-use pump and sensor combo that offers peace of mind when replenishing evaporated water to an aquarium. Its twin optical sensors extend the device’s life and reliability by limiting the frequent powering on and off of the refill pump. This system also includes a third (safety) sensor that provides another level of security to prevent overflows.
The IceCap ATO EZ is a well-thought-out automated system with a fail-safe design that uses two (2) optical sensors to monitor the fluid level of your aquarium or sump. The third optical sensor provides real-time protection against the failure of the second sensor. Best of all, it is very easy to install and contains no moving parts that can fail.
Complete Auto Water Top-off System for Fresh and Marine Aquariums
Everything is provided for installation and operation. You simply move the magnet optical sensor to the desired water level within your sump or aquarium. It’s that easy!
ATO EZ Features:
Ultra Compact sensor - 3/4 x 3/4 x 3/4"
3 Optical Sensors (low, normal, safety)
Magnet Mount
Plug and Play
ATO EZ Includes:
Optical Water Level Sensor with Magnet Mount
DC Refill Water Pump
Power Supply
6.5ft tubing
Universal Tubing Holder
Siphon Breaker
ATO EZ Operation
When the water level in the sump or aquarium drops below the LOW LEVEL (3) on the sensor, it will blink blue until the water level rises to the NORMAL LEVEL (2).
When the NORMAL water level resumes, a solid blue light will display.
SAFETY LEVEL SENSOR (1) is a backup to shut down the feed pump in case of a malfunction; in this case, a red light will flash.
Water Pump Specifications
Brushless DC Water Pump (30000hrs)
Dimensions: 1.5 x 1.5 x 1.5in
Maximum Head: ~6ft
Flow Rate: 50gph
Power: 5w
Tubing Size: ID 6.5mm/OD 8mm/6ft
STEP 1 - Mount the Sensor
Install the sensor with the cord directed upwards into the aquarium or in the last chamber of the sump. Next, move the sensor so the desired water level sits between the second and third inner sensors. Mounts to clear, tinted, or painted surfaces up to 1/2in thick.
STEP 2 - Install Refill Pump
Attach the hose to the output of the fill pump and place it upright into the reservoir. Run the hose vertically to the sump or aquarium without kinks. Do not exceed 6ft total length. Plug the end of the pump chord into the port labeled PUMP on the sensor connection.
STEP 3 - Connect to Power
Attach the power connection to the POWER port located on the sensor connection. Then attach the power adapter to a standard AC wall outlet. The installation of the IceCap ATO EZ is complete.
CoralVue, Inc. and IceCap hereby guarantee this product to be free from defects in material and workmanship for a period of:
1 Year
Warranty is activated on the date of purchase.
This Standard Limited Warranty applies and is limited as follows:
To the product only as long as it remains in the possession of the original purchaser.
To the product that has not been subject to accident, misuse or abuse.
To the product that has not been modified, altered, defaced, or had repairs made or attempted by other than CoralVue, Inc.
That CoralVue be immediately notified in writing within ten (10) days of first knowledge of defect by owner or his agent.
That CoralVue, Inc. shall be given first opportunity to make any repairs, replacements or corrections to the defective construction within a reasonable period of time.
Under no circumstances shall CoralVue and/or the Manufacturer be liable by virtue of this warranty or otherwise for damage to any person or property whatsoever for any special, indirect, secondary or consequential damages of any nature however arising out of the use or inability to use because of the product defect.

Customer Reviews

You must be logged in to post a product review.

Sensor gets stuck on Sep 24, 2023
Very disappointed with this product. It keeps getting stuck on and putting too much RO water back into the tank. In concept it is a great design with a backup sensor all in a small package perfect for a nano tank. At the end of the day, it just doesn't perform. Fortunately, I added another Apex sensor to turn off the outlet on my controller otherwise the IceCap ATO-EZ would have just kept filling my tank until the ATO reservoir was drained. The first time this happened I thought it was just a fluke thing where a baby snail had gotten on the sensor...but this keeps happening with nothing interfering with the sensors.