Got tired of checking water and dealing with fluctuations on 3 different tubs, so I connected them.

I was using three 14 gallon HDX tubs (short version of the 27 gallon, same lids) with six 6" net pots each. It was difficult dealing with 3 separate reservoirs, having to pull 3 plants every day, and then when one tub did well the plants would rapidly change the water. I have a 27 gallon tub, so I could just take the whole top off one and set them on the tall tub, but then I had random air lines stuck in the net pot holes, so that made moving the tops a challenge. Also, of course I was growing algae on the under side of my lids. Hopefully this solves a lot of that.

Here are the materials and tools off the top of my head.

Materials: 3, 14 gallon HDX tubs 600gph air pump 4, 1.5" bulkheads. 2, 6" long 1.5" ID pvc or abs pipe PVC primer and glue Aquarium air line 6 90 degree airline elbows 6 Y splitters 12 small airstones 24 suction cup airline holders small submersible pump flexible plastic tubing black matte primer spray paint for plastic white semi-gloss spray paint

Optional Z-rack clothing rack 2x4's plant light

tools hole saw for bulkheads hole saw for net pots drill deburring tool adjustable plumbers wrench heat gun chop saw for pipe masking tape drop cloth small clean wire brush

I drilled the holes in the tubs as low as I could while still having room to seal. I want to say it was 2.75" on center from the bottom, but can't swear to it. I then used a different longer pipe with bulkhead ends and connected it between two tubs without the rubber seals. Loosely wrapped the bulkheads around the edges with masking tape to keep the heat away. I then layed spare 2x4's across the top of them to hold them flat to the concrete, and then used a heat gun on a low setting to get the plastic hot enough to get "plastic". Mostly above and to the sides of the bulkhead. It took a few minutes on each connection. Had to push out on the tubs at the top, as they were being pushed in by the connections. Let that cool. Disassembled and set all 3 next to each other. The tubs mostly held their new position. Installed the new bulkheads and then measured with a tape measure inside them deciding 6" was the needed length of pipe. Then assembled everything as seen in pics. I was going to run the water pump line outside, but I didn't have any black hose so I just ran it back through the bulkheads. This has much less chance of a catastrophic leak anyways. I also just ran the airlines under the lids, with 90 degree elbows so it can't flatten the line. I used a clean wire brush to texture the surface of the lids after washing and drying them. Sprayed the black on first, waited 48hrs and then did white. The white alone is still translucent, so I sprayed black on the under side. It's definitely easier to just paint the top of the lids black, and then paint it white. That way there is only one surface painted and the black layer stops anything that the white doesn't reflect. That last pic is my tap water before doing anything to it. It fluctuates, but this is as bad as its been.