Here is a repeat of a discussion I started in the mixed design group to interest some people that may not have joined this open group.
The last couple of weeks have been really interesting in terms of reading up on some of the ideas and ideals of aquaponic systems, their designers, and in some cases, their rabid followers (shall I dare say worshippers?). The Australian forums again supplied a bevy of examples of spats and howls around the mention of anything that does not resemble the purist form of media bed backyard AP – a fish tank and media filled beds. Indeed, a heap of component suppliers sell these as their staple thus I assume that there is a great deal of passion (and money) invested in the premise that this is all you should ever need.
By being a member of this group, you already behave ion a deviant manner. Congratulations. I have taken a particular interest in media beds, mineralisation and bacterial action of late. There has been many triggers – seeing some 1 meter deep gravel beds in the IBC pdf, reading hateful exchanges related to suggestions that media beds cannot be plant anchors and mineralisation/ nitrification sites all at the same time, and finally, one of those “special” questions: Where, o where, did the new cast in stone, air tight, more important that the laws of Thermodynamics concept of “thou shalt make a media bed 12 inches deep or else” come from. In both my and my wife’s post graduate studies we have seen similar things happen. Someone, somewhere, makes a statement down the line of “12 inches seem to be a good depth” without trying to say it cannot be 10 or 50, and within a few short citations, the broken telephone of science, it becomes 12 inches or bust.
I’m not interested in going that way. My beds are already too shallow. Sue me. I’m taking an interest in multi-function structures. Swirl filters that become mineralisation sites. Floating media-filled sumps. Deep drums filled with gravel (never to be cleaned again) becoming the first stage of a water source for a gravity fed NFT line. I already have a gravel bed that is also a seed germination bed.
I think that there is way more room for these kind of thoughts than what is typically taking place. Looking at Dr Lennard’s calculator, which I like very much for the components of AP taken into account, not necessarily the ratios recommended, there is always space being made for bio-filter size as a separate entity. I’m going to push this concept a bit this season. I’m planting my gravel beds, but I’m making a whole lot of media-filled structures that will never see a plant and adding them to the system. With raised beds, I have the space for this, and I truly believe that the system can only benefit.