Poor man's ATO - Donovan's cloud switch version

[Donovan Joannes]

Since my chiller went south few months back (80 dollar electrical saving ) and went with fan cooling, evaporation increased tremendously. I was struggling keeping top off level perfect and my wife hates adding RODI several times per day. So I made an auto top off system from scraps I found in my garage.

Things needed:-

Small AC pump (old reactor pump)
Water container (pink lid old plastic container)
Clear silicone hose (left over from my donovan's nitrate destroyers I built for a few friends)
Reef safe stick (took from a broken tent quick setup sticks)
Floating device (styrofoam filled plastic container)
Long arm switch (sliding door wardrobe light switch)
Aluminium angle bar (I have this since the dinosaur time)
PVC coated iron rod (green PVC coated cloths line)
12VDC single pole single throw switch
Standard electrical outlet
12VDC power supply

 

[Donovan Joannes]

First, measure the height of max water level in your return chamber to the cabinet where the switch will be mounted. Cut the reef safe stick 3 inches more than your measurement.

Fill the plastic container (your floating device) with styrofoam. I cut the styrofoam into the container shape and stack several pieces together to form a tight fit. Drill a hole through so that the above said stick will fit nicely through the hole.

Drill several through holes at the bottom part of the stick, 1/2" apart. This will allow you to adjust the float later on.

Drill another through hole at the top of the stick, this will allow the stick to swivel when it moves up and down.

 

[Donovan Joannes]

Remove the roller (if any) from the lever switch (wardrobe switch) and fix the float stick with small plastic rod. I use thick aluminium wire as it doesn't have any contact with SW. Connect the lever switch, 12VDC relay and your AC supply as per diagram. You can connect the AC supply directly to the lever switch, but I prefer a low DC voltage for safety reason.

 

[Donovan Joannes]

Pictures...

Green PVC coated wire as float stick guide. Without this guide, the float stick will move around


Lever switch with carbon fibre stick on it. The aluminium wire ensures the stick can swivel.


ATO pump


The float device. The black carbon fibre stick is 3" shorter, so I grab an orange plastic tubing as an extension. Note the white plastic rods (cotton bud stick), I am using it as float switch adjustment level.

 

[Donovan Joannes]

There you go. Another poor man device for me. Ignore all the mess you see in there. The most important part is the visible display tank...

 

[Cory]

Could i use a float switch instead? Ive got lots already so.

 

[Donovan Joannes]

Could i use a float switch instead? Ive got lots already so.

Sure. Most of the ATO are using one, two or three float switches. Switch in the cloud eliminates stuck open/close conditions. Sometimes snails, calcium build up, bacteria or algae film and gunk build up will disrupt float switch operation. Other than that, nothing special about it.

 

[Cory]

Sure. Most of the ATO are using one, two or three float switches. Switch in the cloud eliminates stuck open/close conditions. Sometimes snails, calcium build up, bacteria or algae film and gunk build up will disrupt float switch operation. Other than that, nothing special about it.

Id like to adapt it to work for skimmate but dont have apex.

 

[Donovan Joannes]

Id like to adapt it to work for skimmate but dont have apex.

Skimmate?. I would rather drill an overflow hole on the cup, and hook up a silicone hose directly to a skimmate holding tank. Put the float switch in the holding tank that trigger the skimmer off when activated.

 

[Cory]

Skimmate?. I would rather drill an overflow hole on the cup, and hook up a silicone hose directly to a skimmate holding tank. Put the float switch in the holding tank that trigger the skimmer off when activated.

Yeah thats exactly what i was thinking. I just dont have the know how with electronics. I hear its as simple as a relay switch in a container with a float valve. Not sure how you wire the pump to it though.

 

[Donovan Joannes]

Just follow my diagram on post #3. I would discourage live AC connection on float switch, always use it as low voltage DC switching for relay activation. Better safe than sorry . Replace the water pump with your skimmer pump to visualize the connection.