CAUTION: This project like many of my others deals with electricity. You should be comfortable working with electricity as well as have a working knowledge of home wiring before attempting this.
This will help you to build an auto top off unit with snail guards. (Note: Some of the information here is from the Louisiana Reef Club
DIY forums
Redirecting...)
Parts
1
PVC box with two 1/2" outlets and cover plate
8 1/2"
PVC 90 elbows
2 1/2"
PVC Caps
2 1 1/2" - 1/2" slip bushings
2 1 1/2" Couplers
2 1 1/2" Caps
1/2"
PVC pipe
1 1/2"
PVC pipe
2 float switches
1 1/4" Polypropylene Solenoid Valve
(These Last two parts can be found on
McMaster-Carr)
Note: if you are using a water pump to top off form a separate container replace the Solenoid with a single outlet 15 amp receptacle and appropriate cover plate.
Step One:
Drill and tap the 1/2" caps to match the float switch threads.
Teflon tape the treads and secure into the caps. (Do not glue. This would make switch replacement very hard.)
Step Two:
Cut eight pieces of 1/2"
PVC 1.5 inches long.
Glue two sets of two 90 elbows in such a manor that they face the same direction.
Glue two sets of two 90 elbows in such a manor that they face opposite directions.
Glue one piece of the
PVC into one end of each of the four sets.
Step Three:
Glue the two sets of same direction elbows to the openings of the
PVC box.
This will provide a manor for the unit to be hung on the side of a
sump/fuge.
Step Four:
Use a rotary tool with a sanding or grinding wheel to trim the inside of the reducer bushing so that 1/2"
PVC will slide easy through the bushing.
Step Five:
Insert the exposed
PVC from the opposing elbows into the open end of the same direction group.
Do not glue! This will allow you to adjust the floats and make running the wiring easier later.
Measure your situation in order to determine where you want to place the switches.
Cut the 1/2"
PVC to the desired length for the longer tube.
Cut another piece of 1/2"
PVC a few inches shorter then the other tube. This will act as a redundancy system.
Step Six:
Glue the caps to the tubes that you have just cut.
Step Seven:
Cut two pieces of 1 1/2"
PVC 1.5" long.
Glue the 1 1/2" caps to the 1 1/2" couplers using the
PVC just cut to bridge them together.
Drill several holes in the bushing and the couplers and caps in order to allow water to easely flow though them.
Step Eight:
Slip the bushing over the 1/2" pipe and cap pieces.
Use a piece of string to thread the wires from the floats through the opposing elbow groups.
Use the string to thread the wires through the same direction elbows into the
PVC box.
Slip fit all of the groups together so that they look like pic 5.
Step Nine:
Drill a hole in the plate of the box just large enough for the solenoid threads to fit through.
Use a nut used for attaching electrical conduit to electrical boxes to secure the solenoid to the face plate.
Drill a hole in the
PVC box large enough to fit an electrical plug through. Ones used for laps are fine. Mine came from an old heater that broke.
Step Ten:
Connect one switch to the power supply.
Connect that switch to switch two.
Connect switch two to the solenoid.
and Connect the solenoid to the other end of the power supply.
Wire nut them together and wrap in electrical tape.
Step Eleven:
Place the over on the box.
Slip the guards onto the bushings.
Screw in two 1/4" quick connects to the solenoid.
Place on the
sump/fuge.
Connect to water supply and plumb into
sump/fuge.
Plug into wall and let the water flow.
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