# Hydroculture/Horticultural aquaponics/Aquatic subsystem

This project is an aquaponic cylinder tank for aquatic animals. Uses can be for a miniature outdoor pond or for a high capacity ornamental fish tank. An external growbed or auxiliary hydroculture unit may be required for this setup. For additional instruction hints, See Horticultural aquaponics/Instructional hints and tweaks.

### Components

All component materials should be nonhazardous/noncancerous. See Horticultural aquaponics/Instructional hints and tweaks
* cylindrical plastic container: new plastic recycle bin, barrel or over-sized bucket
* o-rings
* threaded elbow
* corresponding threaded adapters
* water pump
* washer with screen
* Additional pipe, o-rings and connectors: use 1/2in to 1in pipe and smaller tubing for water flow.
** smaller size tubing and pipes are suitable for drainage. 1in piping offers less restriction, and larger sizes are unnecessary for water flow.

### Construction

For an outdoor aquatic tank an overflow connection with a screen must be installed close to the top. Use two threaded fittings, with a washer with screen in between: it may not be necessary for this connection to be especially watertight.

### Watertight seals

To make a watertight seal: put one o-ring on the male connection, place through hole in plastic material. Then, on the other side of the plastic material, add another o-ring to the male connection, and screw on the female connector. Corresponding components must be of the same size. Connection must be snug. Check for drips.
Threaded fittings with o-rings can reduce or eliminate the need for pipe cement. If the desired threaded fitting is not available in PVC form, galvanized or brass fittings will connect to PVC fittings. Any metallic connector should contain no lead. PVC primer and glue can also be used.

### Water pump options

    Extreme precaution must be practiced when using high voltage components
High voltage water pumps can be a hazard if damaged or mishandled. BLDC pumps are efficient and usually operate on a much safer voltage. An airlift pump may also work, if the aquaponics system doesn't require high water pressure. Use wider diameter pipe to carry the water above the height of the tank, then it can be diverted into multiple smaller channels. No electrical connections or not watertight components may be exposed to water. Plug components higher than water-level or have a drip loop, so water does not drip into an electrical socket or other connection. The choices of how to transfer water from the aquatic tank to the plants are as follows.

#### External

For an external water pump, a hole has to be cut into the side of the cylindrical container, 1/3 way from the bottom.

#### Internal

Make connections from water pump connection to wider diameter pipe, using proper connectors. The pump's electrical wire must be long enough, and it cannot be exposed to potential damage, and the connection away from potential water contact. On the side top of the aquatic tank, drill a hole to insert a threaded plug and o-ring from the outside. From the inside fit on pvc threaded snap tee, o-rings to the threaded plug. The snap tee is to hold the pipe attached to the pump vertically inside the tank.

#### Airlift pump

    See:Horticultural aquaponics/Easy top-drip aquaponics system#Airlift pump
For an airlift pump, smaller diameter pipe or tubing keeps air and water pressure higher allowing water to flow further. This can limit the water-flow pressure, but it may allow the water to travel a farther distance. Micro-sprinklers may be useful as micro-drippers in this case.

### Growbed or component hydroculture

This setup may require an external growbed. Alternatively, this aquaponic setup can connect to an auxiliary aeroponic or hydroponic system.