Outbackozzie has been a member of the Backyard Aquaponics Forum for many years and he’s created a ew classic aquaponic systems utilizing IBC’s. In fact, I think that of the many systems he’s built only his very first system didn’t have any IBC’s in them. Since that first bath tub system, all of his systems have incorporated IBCs to some extent, and more recently with his large commercial systems he has included many IBC’s into the design of the system.
Firstly we’ll take a look at his IBC and Blue barrel system in his backyard. This started as an IBC system, however the IBC’s had to be removed and replaced after a while. Four IBC’s were buried in the ground and a number of Blue 200L barrels were cut in half across their middle to be used as growbeds.The plan for this initial system was well thought out. 4 IBC’s were buried in the ground as fish tank, these were all plumbed together underground so that the tanks could equalize water heights between them.
The IBC tanks on either end had 4500L/h pumps in them, these pumps pumped up out of the IBC fish tanks and down the side of the row of growbeds. The growbeds are 200L blue barrels cut in half around their middle. At each growbed there’s a T in the main line with a riser coming up to the bed with a small valve to control the flow going to each bed.
The growbeds are sitting on bricks, with a main 90mm drain line running down the centre that each growbed drains into. Each growbed has a standpipe and a outer standpipe surround to keep the media away from the standpipe, the system works with the beds being constantly flooded with water to the height of the standpipe. All the main 25mm irrigation pipelines in the system are joined together, and both pumps are actually hooked into the same system, This means that should there ever be a pump failure then the system will keep going, just at lower flow levels to each bed.
To neaten the whole system up and hide the pipe work OBO brought in a lot of dirt, piling it over all the pipe work around the base of all the barrel growbeds. Not only was this dirt going to act as a cover for the pipe work, but also it would act as an insulator from the harsh extremes of heat often experienced in Kalgoorlie.
After some time, a problem with the system became quite apparent, the IBC buried fish tanks were starting to collapse. They had been buried without their steel cages, and without any additional support and the external pressure from the ground especially after rains, was too much and they all began collapsing.
Time for another plan. The IBC’s were removed, the hole dug out a little more and used steel drill rods, a waste product from the mining industry, were used to line the hole. These were welded into place before a rubber pond liner was installed. Now the system had just the one very substantial fish pond, but no IBC’s in the system. A second expansion of growbeds was under way. These were being installed around the corner behind the shed, 4 complete IBC’s with the tops cut out, nstalled as growbeds. This adds a huge amount of biofiltration to the system and another 4sqm of growing area. These beds remain constantly flooded just below the surface of the media, they are filled with blue metal with a layer of expanded clay on top to make it easier to work.
As you can see from all the photos of plant growth and fish harvests, this system has been very productive over the past couple of years in its various forms.