How to Make an Aquarium Float Valve

Float valves are used in aquarium holding tanks. Aquarium float valves are used in automatic top-off systems. These systems maintain the salinity content of the water and remove the need to manually add fresh water on a daily basis to the tank. An aquarium float switch or valve shuts off the water in the sump holding tank when the water line rises to a specific height and turns on when the aquarium needs more water added to the tank.

Things You'll Need

  • 1-inch sprinkler valve
  • 24-volt transformer
  • 1-inch PVC pipe fittings, both male and female
  • 1-inch PVC sprinkler pipe end caps
  • Plastic water holding tank
  • Drill
  • Safety goggles
  • Face mask
  • 1/2-inch drill bit
  • Plastic shoe box
  • Measuring tape
  • Utility knife
  • 1/2-inch bolts
  • 1/2-inch rubber washers
  • 1/2-inch nuts
  • Automatic float switch
  • Wire nuts
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Instructions

    • 1

      Screw the PVC pipe fitting onto the threaded ends of the sprinkler valve. Insert the male pipe fittings into the female ends and attach the 1-inch PVC end caps onto them.

    • 2

      Mount the float switch. Place the switch on the interior of the tank at the level where you want the water feed to shut off. Drill two holes into the side of the plastic holding tank.

    • 3

      Measure the length of the float switch's anchor, which is located at the top of the float switch. Transfer the measurements to the plastic shoe box on two sides near an edge. Design it so that when you cut it out, it makes a corner or V-shaped "guard" for the top of the switch.

    • 4

      Drill two holes on the top of the V-shaped plastic guard to mount the float switch.

    • 5

      Insert the rubber washer and the bolt on the interior side of the holding tank. Tighten a nut onto it on the exterior side of the tank. Insert bolts through the holes of the float switch anchor piece and the top of the V-shaped plastic guard. Use a nut to secure it in place.

    • 6

      Wire the float switch and sprinkle valve according to their packaging instructions. Attach the pump hose line to the sprinkler assembly.