Aquaponics - Home made media

I did an experiment last night where I mixed some clay soil from my backyard with some crushed up goat dung. The plan was to try to make something like scoria, for use as a home made media for a grow bed, but just to see if it could be done.

And voilĂ !

First, I spread some whole dung out on a tray. Then I made a mixture of clay,water, and powdered goat dung. My theory was that the powdered goat dung would create thousands of tiny holes in the finished product. This would create some happy housing for the nitrifying bacteria required by aquaponics.

I then poured the mixture over the tray of whole dung. The design behind using the whole dung was an attempt to make it break into irregular shapes later on in the process.

Next I set it out to dry. If I was making an amount greater than this tiny test, I would have poured it onto the ground in the sun. But it was raining so I put it on some foil, and dried it on the fire. DONT DO THIS AT HOME! It can smell a little agricultural. When the yelling stops, you know your tile is dry.

Lay it out and build a fire over it. You want your fire to be 900 deg C or more. Clay will undergo a permanent chemical change at around 600 deg C (don't quote me on that number) where it becomes no longer possible to wet it back down to clay. The physical water steams off at 100 deg C, but at those higher temperatures its not just drying the clay, it's actually changing it into something else.

I actually fired mine in my living room wood burning heater, but to make it properly you need the kind of temperature that makes iron glow bright cherry red (~900C) It's quite doable in a decent fire.(a match burns at around that temperature).

A normal pot would crack if treated like this but because there is so much organic matter leaving the clay body porous, we can get away with it. It doesn't matter if it cracks anyway.

Next. Smash it.(see)

Its done (see top pic)


I have no idea if this is practical or useful in any way to anyone, but it was in my head so it had to come out.

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