 Recycling the water is a critical component of nearly all aquaponic systems. This system depends on a pump and plumbing fittings to move the water from the fish tank up to the plant grow bed. And the bell siphon and gravity control how the water gets back to the fish tank. In most cases, cycling all of the water through the system every hour is sufficient to maintain the water quality and provide adequate nutrients to the plants. Attach one half of the half inch union fitting to the one half inch outlet of the pump. Using a union fitting next to the pump makes it easy to remove the pump for any maintenance that might be required. On the other half of the union fitting, attach the fitting that has one half inch threads on one side and a three eighths inch barb on the other. Next, connect the three eighths inch flexible tubing. Attach the six foot piece of tubing to the barb. Using a flexible hose instead of hard piping allows more possibilities for rooting the pipe work to move the water from the fish tank to the grow bed. On the other end of the three eighths inch tubing, attach a three eighths inch barb to male threaded fitting. Screw the threaded end of the fitting onto a half inch 90 degree elbow threaded on one side and designed as a slip fitting on the other. Push a three inch piece of half inch diameter pipe into the slip side of the elbow. Push another 90 degree slip elbow on the other end of the three inch pipe and turn it downward. Add another three inch piece of half inch pipe and a third 90 degree elbow turned outward. Having this U shaped configuration on the end of the grow bed water delivery system makes it possible to hang it over the side of the pre-filter you'll build next. Connect the two halves of the union fitting together next to the pump. Using a pre-filter between the fish tank and the grow bed will help prevent solid fish waste and other particles from clogging up the growing media which can cause channeling and result in uneven water distribution. If the media gets too clogged it must be removed and cleaned. Drill a one and three quarter inch hole in the center of the bottom of the one gallon bucket using the electric drill and hole saw. Insert a one inch uniseal in the hole. Lubricate the seal with a silicone lubricant and push the four inch long piece of one inch pipe through the uniseal until there are two inches on the inside and two inches on the outside of the bucket. Place a three inch net pot upside down over the top of the pipe on the inside of the bucket. This ensures that the foam pad will not cover the opening of the pipe and will allow water to enter through the sides of the net pot as well as the bottom. Push the foam disc into the top of the bucket so that it forms a bowl. Do not push it down onto the top of the upside down three inch net pot.