My apologies for the delay on this, but at long last, here is my update on the aquaponics set up. I mentioned before that my model is based on the information I found on a YouTube video (check it out here). I decided to use a 4-inch stand pipe, but once we added all of the couplings and stuff, it ended up being about 5-inches tall (not including the screw part that fits through the bottom of the tub to attach the drain spout).
The bell siphon is made of 2" PVC and is 6-inches tall with the cap on. The holes in the bottom are about 1/2 inch up from the bottom. We did end up making them larger after I took this photo.
The media barrier is 4" PVC and we drilled holes randomly throughout the entire thing, even above where the water level would be, just in case. Below is a photo of the set up with just water running through it (no gravel).
We used four 20" 2x4 boards under the aquaponic tank to help hold the weight of all the gravel. I did make some modifications. Originally the drain spout ended up under water when the tank was full (as the aquaponic bed was emptied). This caused issues with the bell siphon not breaking the seal and constantly just sucking up water from the "empty" point (1/2-inch). So I shortened the drain spout (it now sits about 2-inches above the water surface at the fullest point).
After a few more issues with the water hose falling out of the bed, the water pump not wanting to cooperate, and the siphon occasionally sticking, I think we've got everything up and working properly. I added the pea gravel (rinsed first) yesterday, burying the end of the hose to keep it in place. It seems to be running well now. It has been taking just under ten minutes to complete a full fill/empty cycle.
Now I just need to get a lamp above, and get some seeds planted. More updates to come. My thanks to Tony for doing most of the assembly and cutting for me.
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