Step 1: Hardware
Goal: Acquire all the pieces for the physical system, including a way to pump solution into it
9 containers
1 ten-foot piece of pipe, 1-inch SCH-40 PVC
1 PVC cutter
8 1x1x1 tee fittings, 1-inch SCH-40 PVC
4 1x1 90° elbow fitting, 1-inch SCH-40 PVC
2 1x1x1 side outlet 90s, 1-inch SCH-40 PVC
1 1x1x0.5 reducing tee, 1-inch SCH-40 PVC
1 0.5x0.5 spigot barbed adapter, 1-inch SCH-40 PVC
1 5’ flexible PVC pipe, 1-inch SCH-40 PVC
Various other PVC fittings used for attaching my containers, which will vary with any setup depending on the containers themselves and the specifics of the system
PVC cement
Black Krylon Fusion (for plastics) spray paint
Matte brown spray paint
Aquarium sealant
Stainless steel faucet screens
15’ one-half inch aquarium tubing (it’s cheap so I got extra)
Submersible water pump
Solution tank (opaque, lidded plastic storage bin)
Equipment I had on hand included a variable-speed Dremel tool with an aluminum oxide grinding bit, a drill, a drop cloth, a fan for extra ventilation near the workspace, latex gloves, a piece of scrap wood, and lots of masking tape.
First, I prepared the containers by drilling a ¼” hole in the bottom of each, with masking on both sides, and with the bottom of the container up against the piece of scrap wood. Trying to drill with the container upside down would be folly; plastic cracks very easily when drilling. I’d recommend going slowly, and getting an extra container or two just in case. I was glad that I did! Using the Dremel and grinding bit, I carefully widened each hole to accommodate the fittings I’d decided to use to support the containers and supply nutrient solution to them. Finally, after thoroughly washing and drying the containers, I masked a ½” strip along the side of each, so after they were painted I’d still be able to monitor root systems and solution levels. I also placed a small piece of masking tape over the bottom hole, on the inside, to prevent spray paint from entering the container.
I cut all the PVC to the specifics of the system I’d designed. Before gluing, I laid them out end-to-end on my table, giving me a chance to make sure they’d fit, as well as to ensure I had everything I needed.
I then glued them all together. (Research this process well before you attempt it; PVC cement sets within seconds and once it’s set, it’s really freakin set.) With eight tees facing up – seven for containers and one for overflow – and the two side outlet 90s facing up, I had spots for 9 containers. I had 
cut the overflow pipe to match the top of the growing medium I’d have in my containers. I attached an elbow to this pipe, then another short pipe length, another elbow pointing downward, and, finally, the flexible PVC that would take used solution back to the container. The spigot barbed adapter, which would be used for intake, was pointing horizontally out one side (well… almost horizontally! I’m telling you this glue sets quickly!).
I painted the system black, so it would look sleeker, being sure to close off any openings with masking tape so
no paint could get inside. To ensure opacity of the containers, which is necessary for roots, I primed those with the black Fusion paint and then gave each two coats of the matte brown (which was actually a primer, but served the purpose and gave the containers a terracotta look as an added bonus).
I then attached the containers to the system, with their male-threaded fittings coming up through the bottom and the matching female fittings anchoring them down. I sealed these connections with aquarium sealant
(three coats) to ensure there’d be no leakage. I had some neoprene washers that I’d been planning to use to help ensure a watertight seal, but, in the end, decided that this would be overkill with the PVC cement lining the threaded connection and aquarium sealant around it. (In retrospect this may not have been overkill, since the threaded PVC connection is not flush; the glue set before I could twist them all the way down.) I pressed the small circular faucet screens down into each connector so the clay pebble medium I’ll be using wouldn’t drop in. They fit perfectly, and as of this writing I’m hoping that they won’t be under so much pressure that they’ll push through. We’ll see.
After allowing the aquarium sealant to cure for the recommended time, I tested the system in the bathroom using the sink for intake and the tub for overflow. It took about 4:30 for the system to completely fill (to within ½” of the top!) and about 3:30 for it to drain. This is with the entire 15-foot length of tubing, with the system not too elevated over the pump, with the overflow tube flowing on a curve, and with no growing medium taking up much of the space in each container, so both times will probably be slightly faster in the end. Two minor leaks on the aquarium sealant need correction but other than that it looks like I’m in business! When the system is set up, the pump will be submerged in the tank and the overflow pipe will drop solution back into it, from a level above the top of the solution to help oxygenate it.
cut the overflow pipe to match the top of the growing medium I’d have in my containers. I attached an elbow to this pipe, then another short pipe length, another elbow pointing downward, and, finally, the flexible PVC that would take used solution back to the container. The spigot barbed adapter, which would be used for intake, was pointing horizontally out one side (well… almost horizontally! I’m telling you this glue sets quickly!).I painted the system black, so it would look sleeker, being sure to close off any openings with masking tape so
no paint could get inside. To ensure opacity of the containers, which is necessary for roots, I primed those with the black Fusion paint and then gave each two coats of the matte brown (which was actually a primer, but served the purpose and gave the containers a terracotta look as an added bonus).I then attached the containers to the system, with their male-threaded fittings coming up through the bottom and the matching female fittings anchoring them down. I sealed these connections with aquarium sealant
(three coats) to ensure there’d be no leakage. I had some neoprene washers that I’d been planning to use to help ensure a watertight seal, but, in the end, decided that this would be overkill with the PVC cement lining the threaded connection and aquarium sealant around it. (In retrospect this may not have been overkill, since the threaded PVC connection is not flush; the glue set before I could twist them all the way down.) I pressed the small circular faucet screens down into each connector so the clay pebble medium I’ll be using wouldn’t drop in. They fit perfectly, and as of this writing I’m hoping that they won’t be under so much pressure that they’ll push through. We’ll see.After allowing the aquarium sealant to cure for the recommended time, I tested the system in the bathroom using the sink for intake and the tub for overflow. It took about 4:30 for the system to completely fill (to within ½” of the top!) and about 3:30 for it to drain. This is with the entire 15-foot length of tubing, with the system not too elevated over the pump, with the overflow tube flowing on a curve, and with no growing medium taking up much of the space in each container, so both times will probably be slightly faster in the end. Two minor leaks on the aquarium sealant need correction but other than that it looks like I’m in business! When the system is set up, the pump will be submerged in the tank and the overflow pipe will drop solution back into it, from a level above the top of the solution to help oxygenate it.
Here's the finished system!
This step was fairly inexpensive to accomplish, but complicated from a technical point of view. The next step I’ll detail, setting up the growing environment, will be far simpler in terms of engineering, but will involve the most expensive elements.
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The system is bigger than it looks for those lookin' at the blog!
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