Today, I worked to get the plumbing set up on the two cone filters of the aquaponics system.
I started the build by cutting an x into the bubble foil insulation I have around the main tank. I need to pass a 2"ID pvc pipe through the tank.
Using a 3" hole saw I created a hole near the top of the fish tank where my overflow standpipe will be placed.
The hole center is around 24" measured from the bottom of the Inside of the tank.
This measurement determines where I will cut the length of the pvc standpipe as well. I want the standpipe to rest about 1/4-1/2" off the bottom of the tank to pull out the fish poop solids, but prevent any fish from getting sucked into the pipe. The standpipe is a standard 2" pvc T-fitting and 2 sections of 2" pvc pipe cut to 24" and 5".
The next step was to apply some dish soap to the front of a rubber uniseal for 2" pvc. The pvc is almost impossible to push through without using the dawn dish soap or some type of similar soap.
A bevel needs to be put on the end of the PVC that will get pushed through the uniseal. More soap applied will aid you in getting the pipe inserted through the seal. That pipe assembly gets pushed through the uniseal in the main tank and will be connected by 2 90deg elbows to the cone tank.
The next step was to create the hole in the first cone tank. The hole needs to be about 1' lower than your exit from the main tank which puts the hole center on this set-up right at 3" from the plywood of the stand. I made a line mark with a pencil and used the peice I cut out from the main tank as a template to mark my center hole.
Using the hole saw I created the hole for the over flow water to enter the first cone tank.
The uniseal is pressed into place.
A section of pvc is measured between the main tank and the inside of the cone tank. The pipe needs to go just inside the tank so the water will create a spin from entering from the main tank.
Which will look like this, it can be longer to extend to the other side of the tank if you wish. The point is to get that water to circulate in the tank giving the incoming solids a chance to fall toward the bottom of the tank.
Here's what the outside looks like after that is complete.
The next hole will be where the water will spill out into the next tank. It should be slightly lower than the exit of your overflow standpipe. On this system it was around 14" from the top of the lower pipe to the center of this hole.
Another uniseal is pressed into the hole, any stray pieces of plastic that are still left in the hole should be cleaned out before the uniseal is inserted.
Another section of PVC is inserted into the tank this one needs to sit closer to the center of the tank and for these tanks it's about 18" which gives you about 4" on the outside of 5he tank for a 90deg elbow and a section of PVC that will connect to the second tank.
A 90 degree elbow gets attached pointing up inside the tank and should look like this.
Use a section of PVC that will reach the bottom of the second tank.
I measured the distance of the holes from the surface of the tank stand. The holes centers are 3" and 18" from the surface of the stand.
I translated those measurements to my other tank to cut those holes.
Here is the mark for the top hole.
I inserted the two uniseal and pvc sections repeating the previous steps. I used an old section of PVC assembly to layout how the overflow pipe will run to the next step which is the creation of the media bed and sump.
Thanks for checking out this post! I hope this may aid anyone looking to build their own backyard system. Tune in tomorrow for the Meadows and Makers Podcast I host on mspwaves.com from 5-7pm UTC 1-3pm EST. Tomorrow's guest is a returning friend, and my aquaponics mentor 
Yours in Liberty toward a brighter future,
Greg Doud @makinstuff