Backyard Aquaponics
A place to discuss aquaponics

Does that have the opposite effect to wedding cake???

hope so........................

Another advantage of anaerobic microenvironments is the reduction of iron by another set of bacteria. These bacteria reduce iron from ferric (Fe3+) to ferrous (Ferrous) the form usable by plants. They are obligate anaerobes. When you dig down into wet (anaerobic) clay soil you will see a transition from red-orange of ferric iron to gray-blue-green of ferrouc iron. That’s the work of these bugs. With out the anaerobic areas all the iron will be locked in to an unusable form unless it is cheated.

Yes..yes Effigy..... now I remember reading an article that said that...

Such a complicted, scientific report that I didn't take it all in at the very late hour I tried to read it.... will have to dig it up again.

So does that mean I should bury a few rusty nails into my growbed? I never bothered because concensus here a while ago was that it wouldn't be absorbable by the plants. This means it would be broken down. OK, where did I leave my rusty nails...

now we're getting serious! Kepp it coming kids!

Effigy/rupe can you link to a document?

JP, this is going to be a very valuble thread indeed! i'll have to stop my silly comments that are cluttering it!

I came across the information initially reading The biology of soil : a community and ecosystem approach by Richard D. Bardgett.
https://www1.lib.purdue.edu/cgi-bin/Pwe ... 1847&SID=3
It is very fascinating read so far.

My further web search on the subject turned up this abstract about identifying the responsible microbes.
http://www.cosis.net/abstracts/EGU2007/ ... HPSESSID=e

And this article about the coupling of iron and nitrate reduction.
http://soil.scijournals.org/cgi/content/full/71/1/108

The iron-nitrate article is probably the more significant one for AP since nitrate is so abundant. It investigates the observation that ferrous iron(II) production is inhibited by the presence of nitrate and explores several hypotheses that might explain this. Unfortunately this probably means that AP will be unable to fully take advantage of this part of the iron cycle.

Not the article I'm thinking of... but a couple of links to the "iron" reference....

http://aem.asm.org/cgi/content/abstract/51/4/683

http://mmbr.asm.org/cgi/content/abstract/55/2/259

http://crops.confex.com/crops/wc2006/te ... P18486.HTM

http://www.uni-giessen.de/fbr09/mikrobiologie/siron.htm

http://www.geobacter.org/publications/T ... y_1993.pdf



This article might suggest that AP may prevent this iron mechanism....

http://www.pubmedcentral.nih.gov/articl ... tid=377882


There seems to be a link also between Iron, Sulphur & Phosphorus


http://www.ingentaconnect.com/content/k ... 1/00002343

http://www.publish.csiro.au/paper/SR9930493.htm

Ummmm.... this may have been the article.... too late at night to read it through.... good luck.....

http://jeq.scijournals.org/cgi/reprint/32/4/1306.pdf

Hmmm. I have just skimmed some of these articles so far.

If you ran a low-nitrate system, and added rusty nails, maybe you could alleviate iron-deficiency in the plants, and get better-tasting fish (Per the Bathtub Purging Experiments).

Good thread! Thanks Janet for sharing. Around here, I am the smart guy. I am the only one that knows anything about AP.... that is really scary.

My experimentation suggests that rust does not dissolve in water in useful quantities.

We're not talking about rust dissolving, seems like the bugs do the conversion work to a more soluble form of iron than "rust"

Exactly, Steve. I'm also thinking that it would take time to get a proper culture of "rust bugs" established. Just like establishing your basic "nitrogen cycle bugs". I've dropped some rusty horseshoe nails, washers and a spring to the bottom of one of my standpipes. They will be continually wet there, and can hopefully develop the anaerobic micro-environments. I figure there is no harm in trying it. Until I can get the nitrates down a bit, and the "rust bugs" establish (or not) I will add chelated iron as needed. When I realize I haven't used chelated iron in 6 months, maybe that means the "rust bugs" established.

I have been having a recurring problem with iron deficiency. My current theory is that since tilapia eat veggies rather than meat, there is less iron in their diet and therefore less iron available for the system. The greensand has just not been enough, and I upset the fish again with kelp tea.

I think I'll run the ideas here past the Really Smart Guy (RSG), and see what he thinks.

Boy that would be great!. It would save me brown water and having to look so hard for chelated iron. Lots of rusty things around here, Lots of bugs too. Now if I can just find some rust bugs.

JP, remember when i said that i have NEVER added iron (chelated) i'm thinking now.............my VERY first attempt at a system had the same inground IBC as my current one. It had a black tub sitting ontop of two pieces of rusted angle iron with water falling back to the tank over the iron.

Am thinking now that this fine rust has been trapped in the bottom of my GB. In light of the anerobic microclimate comment maybe this is why i've never needed iron? all the contents of the original test bucket went into the current GB.

If you were to bury iron anywhere i'd say in the very bottom inch of your GB as this is probably the most anerobic (relatively) part of the GB.........

keep in mind the small amount of iron that we actually need, we're only talking a few ppm every time you add chelated iron..............

I'd be more inclined to rust up some steel wool (in a bucket with water and a bubbler works wonders) and then pour this into your GB. You will have given the bac the insoluble Fe2O3 which they can then convert.