Agri Kultuur January / January 2018 - Page 23

INSIDE THE CANAL: • Measure 150mm from the side of the canal centre across the width of the canal as indicated in the diagram above. Mark a dot at the bottom with your permanent marker. • Drill a 25mm whole in with a hole saw and lightly sand down the edges to remove the fluff. • Cut a 25mm running nipple in half (keep other half to use on another canal) and place it in the hole. • Place a rubber gasket on either side and fasten the running nipple with 25mm PVC locknuts. • Attach a 32mm x 1” Adapter Socket (Female Thread) on either side. • Inside the tank, insert a 25mm PVC pipe in the adapter and measure the vertical distance of 300mm from the bottom of the tank. Mark this length and cut three standpipes to size (additional two for the other two canals). • Once inserted, cut a 320mm piece of 50mm PVC pipe. Cut slots 15mm deep into the pipe at 20mm. Once completed, place the float guard over the 25mm Standpipe. BELOW THE CANAL: When designing a system using gravity flow, it is very important that drainage pipes must AgriKultuur |AgriCulture run at a slight angle, usually a minimum of 1mm for every 100mm (1: 100) of length to the lowest point. In our case, our water levels balance out on atmospheric pressure on the surface of the water. The water levels in the canals are higher than the 50mm outlet in the biofilter thus trying to balance out the water levels by forcing the water out. • Cut three lengths of 25mm pipe 100mm long and insert one length into the bottom adapter. The other two is for the other tanks. • Attach a 50mm x 25mm Reducing T-junction Solvent Socket to the 100mm pipe. Do the same for all three tanks with the 50mm sockets of the T’s following the run of the drainage pipe (see previous diagram). • Once done measure the distance between the shoulders of the reducing sockets and add 25mm either side to compensate for the insertion of pipe into sockets on either side. • In canal 1, insert a T-junction in line with the biofilter and cut a piece of 50mm pipe after measuring the distance between the head of the T-junction and the socket of the biofilter. Construction of Water Inlets: The water is pump via a 32mm PVC pipe from the biofilter and the flow split into a T-Junction, 20% to the DWC canals and 80% 23