Well after almost a year of trial and mainly failure I am getting serious, Grow Beds (from the brilliant Backyard Aquaponics Shop in Jandakot Ph: (08) 9414 9334 ) will be here this week and 2 x 3000lt poly tanks are here already and have 10,000 Litre per hour tornado pump on the way so thought I would get my thread started and unfold the plan.
The last twelve months hasn't been a complete failure as I was also experimenting with native fish, marron, freshwater shrimp and mussels etc to see if I could build a mini eco system like the ponds and dams these things live in naturally, well i think this was successful in a 2000lt tank and also a 200lt bath tub with goldfish also
I am no good at Google sketch so I will use Nocky sketch, I describe it and you draw it in your mind , I am having 2 x 3000lt tanks joined at the bottom by 80mm bung holes and PVC, tanks will have about 2" of blue metal in them, this is mainly because people I know that tried marron in poly tanks discovered that the poly rubbed the marrons tail fins off so the couldn't move around much at all The bottom connecting pipe will have a mesh over it to try and stop fish changing tanks a little, in 1 tank I am going to have my ECO system growing Pygmy Perch, Marron, Freshwater Mussels and Shrimp and other swimming insects, this system looks after it self, I have one at 2000lt that is clear and has minimal GB area, in tank 2 I will have Mussels and Silvers or Jades, some Black Bream and shrimp from tank 1 which is also grown as fish food. I have 1000lts of grow bed, I know most will say not enough but room for expansion, The idea is to pump from tank 2 the FT through the grow beds and drain into tank 1 the Eco Tank with the idea that what the GB's miss, the Eco tank will clean up, I will next year add GB's if needed or not, basically we like our native fish, marron and Eco idea and want to grow edible fast growing fish and better Veg, the Eco set up's we have appear to be too clean even the small one with 6 big goldies.
I have a 10,000lt Per Hour pump that will have very little head so should get about 8000lph and haven't worked out what times to cycle the pump yet and I am open to suggestions, I also have a 2 outlet battery back up air pump that will rum 24/7.
This will happen starting mid February and will post pic's as things progress, I also am looking forward to emptying my existing tank to see how the Mussels Bred and also the Blue Marron, this will happen in April sometime.

Look forward to seeing the progress Nocky! Watch this space

Nocky sketch
I've got a 10000lph pump in my system. I stepped it up to a 2in black pipe that will connect to a swirl filter if George will only move out. I've noticed a lot of crap building up in the bottom of my yabbie tank. If you plan on running the pump 24/7 you could divert some flow at less than zero head to keep a lot of the solids moving. Then just restrict the flow to determine the GB f&d times. Which tank is the pump going in. And can a no holes overflow or something else be used to pull solids from one tank into the other with the pump in it.

Duff on a smaller scale the Bath tub has the same setup with blue metal on bottom and no scum build up since putting in mussels and natives in fact the water is crystal clear, growing apple mint in a sink grow bed with same system as well and all is going great

Well February almost gone and not much action, Grow Beds Finally here and still need to pick up the tanks, but the area I am using has been cleaned up. I am now going for a 12-15000lph pump with the idea of running it 30mins on and an hour off, Duff I am sort of hoping the pump will have enough flow to drag the solids around and also the mussels well sort them a bit as well, plus marron eat poo as well.
Questions:
1) What are my suggested pump times like?
2) Will the GB's empty as fast as water is pumping in?
3) Is this a disaster waiting to happen?
4) Where is "OBO" ?

5)Where are all the pictures.

Since you asked Duff here is progress Pic number 1 hot off the press

Obviously a fair bit of thought gone into that set up
with a few emu nests happening

I wonder if they'll breed, and overpopulate, or just move on as more are created

Well OK if you insist, for you C1

There was also talk about putting something on the bottom of the tank to allow mussels to dig themselves in - did we ever get any definiative results? Can they dig into blue metal?

I dont know about blue metal but they can certainly manage heavier type aquarium gravel, so I am guessing that provided the metal doesn't pack down too tight, they should be fine, as long as they have no advers affects from the metals trace elements.