As many here know, I am an advocate for simplicity. What I would do to change your design would be to eliminate the swirl/bio-filter, run the water pump lines directly to the grow beds through control valves. Return the extra water from the pump to the fish tank under pressure through a reduced (end cap with drilled hole) outlet, thereby jetting some water back into the fish tank for added aeration. This modified arrangement will require ample pumping power. You will need the extra water flow in order to purge the lines running to the grow beds every few days to remove accumulated fish solids by fully opening the valves to the grow beds.
Be sure to use ball valves and not gate valves. We have learned that even though gate valves give you a finer increment of adjustment when setting the flow into the grow beds, they don't remain where you set them; and they are more expensive. With ball valves, the flow remains constant as long as the pressure doesn't change.
Make sure that your grow beds (and now bio-filters) are 12 inches deep and filled with media (I prefer Hydroton, but gravel will work) to allow the fish solids to break down over time in the grow beds. This will give your plants extra nutrients and reduce your work load and wasted water. For this to work, it requires ample aeration.
This design is all spelled out in Aquaponics 101, located on this forum, including sizing your air and water pumps.
It is important that your fish tank receives ample light, as Tilapia do better with light. Do not be concerned with algae growth in the fish tank from the light, for the Tilapia will eat it unless they are being over fed.
You've pretty much confirmed the path I should take. My original design didn't include the filter and I'll give it a pass unless I need it down the track. e.g. I want to 'overstock' with fish.
Good to know about the ball valves.
My grow bed design is 12" so that matches you comments. Nice!
Good to know about the light requirements too. I don't think that will be a problem here in AZ as we have PLENTY of light. I am concerned about the water getting too hot here, thus the shading by the grow beds and also one reason for sinking the fish tank in to the ground.
I've read hours and hours of forums and how-tos, and I think it's about time to start piecing some lumber together.
Home depot has EPDM liners by the foot.
+1 on the danner pump. The quiet one 3000 is junk.
Unless someone like you cares a whole awful lot, nothing is going to get better. It's not.-- Dr. Seuss, The Lorax
Simplicity of character is the natural result of profound thought~fortune cookie
Anybody know whatever came out of this? Would be nice to see an update.
At first I left this blank...but now I believe: "It's better to keep your mouth closed, and have the world think your a fool, than open it and confirm it."