FAQ

ATO Controllers
    Standard
    Longwire
    12 Volt
    Custom

Mounting Brackets
Float Switches
Pumps & Tubing
Solenoid Valves
RO Fittings & Parts
Miscellaneous

A water level controller (ATO) with a mounting bracket, a reservoir, a pump and some tubing.

The controller turns on power when your water level is low and turns power off when your water level normal. Plug a pump into the controller and it will power the pump when needed to keep your tank's water level constant.

A controller can have multiple sensors. It can do other things too like turn off power to your return pump if your tanks level goes high or your sump level goes low or shutoff your skimmer pump if the collection cup is full. With the custom latching option, you can set the water level range which is useful for preventing your RO system from running for short intervals and in ebb flow hydroponics.

You can reverse the operation of a float switch by reversing the float. When you remove the float and look in the hole you can see the magnets inside, they go up for normal operation. Installing the float with the magnets down will make the controller turn on power when the float is high and turn off power when it goes low. 

Setup a reservoir for topoff water and put a pump in it. Run tubing from the pump to your tank or sump. Hang the bracket in your tank (or sump if you have one) and tighten the nylon set screw to secure it. Attach the float switch to the bracket at the height of your water level using a zip tie. Attach the second fail-safe float switch to the bracket higher than the primary switch. Plug the pump into the controller and the controller into the wall. Presto!

Keep the relay box dry. Mount the relay box high so water can't run down the float switch wires and into the box (or install a drip loop on the switch wires).

If you're using a solenoid valve instead of a pump and reservoir, you'll need to tap into your water supply and run tubing to the solenoid valve and then to your tank.

A GFCI (ground fault circuit interrupter) monitors the amount of current flowing from hot to neutral. If there is any imbalance, it trips the circuit. It is able to sense a mismatch as small as 4 or 5 milliamps, and it can react as quickly as one-thirtieth of a second.

Electrical devices that contact water should be plugged into a GFCI.

You can install one yourself

Yes, there are holes drilled in the bracket so you can attach the switch where you need it. If the holes aren't where you need them, drill some more or zip tie around the whole bracket, use glue, etc. Do not use magnets...They interfere with the operation of the float switch.

Measure the max thickness of the top 1" where the bracket will hang over.

0.5" brackets fit tank lip thickness 0" - 0.5"
1" brackets fit tank lip thickness 0.25" - 1"
1.5" brackets fit tank lip thickness 0.75" - 1.5"

Standard brackets are 2" wide. Nano brackets are 1" wide. You'll need a footprint of approx 2.25" x 2" to mount an standard float switch or 1.75" x 1" for a Nano switch. Check our float switches page for dimensions of each switch.

You can make your own bracket using our plastic stock on our brackets page. Bend it using a propane torch or heat gun. Heat both sides slowly until soft then wrap around a block of wood and clamp in place until cool.

Yes, email us and tell us about your requirements.

About 1/8" change in water level will trigger the switch. A double switch controller with the custom latching option will allow you to set how much water level change will trigger the controller.

The PVC surround on the lower switch will help prevent excess on/off switching caused by waves. There are 2 vent holes drilled in the top of the pvc guard that surrounds the switch. Partly plugging the vent holes will slow the water flow getting to the switch and further prevent excess switching. You can also add a snail guard to the bottom of the lower style switch.

The extra switch acts as a fail-safe in the event the primary switch gets dirty and sticks. The second float switch provides an extra layer of protection by shutting off the controller if your lower switch fails and your water level triggers the second switch.

Inspect often and clean as needed.

Remove the plastic retaining clip that holds the float on and clean the parts with water and/or vinegar and a q-tip, pipe cleaner, etc. The float is reversible so take note whether the magnets inside the float are on the top or bottom so you can reassemble correctly (Magnets go up for normal operation). Don't forget to clean the 2 vent holes in the PVC surround.

10 Amps = 1200 watts. You can also use a power splitter and plug multiple things into it.

If your topoff reservoir is taller than your sump you may need to make a siphon break so your topoff pump doesn't start a siphon between your reservoir and your sump which would continue until the two water levels equalize. To prevent a siphon, find a way to allow air to enter the tubing above the max level in your reservoir.

One method is to put a piece of pvc pipe in your sump that goes up as tall as the max water level in your reservoir, then insert flexible tubing from your ATO pump into the pipe. This allows an air gap where the pvc pipe and flexible tubing meet which will break the siphon. You could also poke a hole in the tubing (and figure out a way to deal with the water the comes out of the hole when your topoff pump is running).

It's an electronic water valve capable of handling the higher pressure of your plumbing system. Typically you'd use a Normally Closed (NC) valve instead of a pump and reservoir which eliminates the reservoir and having to refill it.

A Normally Closed valve opens when powered, and is closed when not powered.

Direction Matters! Install so the water flows in the direction of the IN / OUT or ARROW markings on the valve.

Have a fail-safe! We like flow-lok leak detectors and leak controllers. We sell them here.

We warranty our topoff controllers for 2 years (and sometimes longer)!

If you have a problem with yours, please email us: AutoTopOff@gmail.com

We will not be held liable for the misuse or failure of our products.

Contact Us: AutoTopOff@gmail.com