Wednesday, July 3, 2013

Facultative anaerobes removing phosphates PO4 from a Koi ponds water.


The Brits are getting cleverer! Just over a year ago, when I first started writing about your anoxic filtration system, I had to make sure that I used non-scientific expressions where-ever possible. Few people seemed to understand the concept and I didn't want to frighten the rest away. Now things are at last changing. The questions I am being asked are getting more technical.

Here's a question that made me think: If facultative anaerobes can remove nitrate (NO3) from the water by stealing the oxygen and leaving the nitrogen to eventually escape to the atmosphere, can they remove phosphate (PO4) in a similar manner?

I think they might be able to use the oxygen, but if you take all four oxygens from PO4, you will be left with a single P (phosphorous) which will remain dissolved and not gas off like nitrogen. Then I started wondering, would any of the bugs in the biocenosis baskets metabolise the phosphorous and complete the phosphate removal process?


A couple examples of Phosphate test kits. 


Syd, here are some quotes from the pages of my New CD-book that more than likely answer your questions. Sorry about bringing up the book again, but I did try to cover all the bases when I wrote it. Also, Dr Franco’s tests he did in Italy did show that his PO4 did go down when using the Biocenosis Baskets in his experiments. (Ed.-The Cd-book is no longer available but is available in Apple’s iBooks library for free.) 

It’s good to see that the Brits are thinking, and not just jumping to all kinds of inaccurate conclusions. Phosphates are most commonly found in the form of adenosine phosphates such as AMP, ADP and ATP and in DNA and RNA and can be released by the hydrolysis of ATP or ADP respectively. If you read the quotes that I’ve listed, it will be explained a little better. 

Once again thanks for your astute question, I hope this helps! I know that you can bring all that is said here into a better perspective for the Brits than I can, I do lack your professional one-on-one communication skills. 


“Anaerobic heterotrophs reduced nitrates back to ammonia, and no further period. They are very inefficient at the use of phosphorus for energy, resulting in abundant amounts of phosphates.
 (But not so facultative anaerobes - Ed.)” 


“The fact is that when glucose is randomly added to these facultative anaerobes they have an Adenosine Triphosphate (ATP) yield of approximately 34 times that of anaerobic heterotrophs. Adenosine Triphosphate s corresponds to the speed and efficiency nutrients can be reduced to make energy. Organic carbons do not limit these bacteria and mineral nutrients as heterotrophic bacteria are, which will have a negative impact on other chemolithotrophic processes.” 


“1: In aerobic organisms, oxygen is used as a thermal electron acceptor during respiration. This is largely because oxygen has a very low reduction potential allowing aerobic organisms to use their electron transport systems most efficiently. In anaerobic organisms, thermal electron acceptors other than oxygen are used. These inorganic compounds have a higher reduction potential compared to oxygen, meaning that respiration is less efficient in these organisms generally leading to slower growth rates compared to aerobes. Many facultative anaerobes can use either oxygen or alternative thermal electron acceptors (like nitrates) for respiration dependent on the environmental conditions. Most respiring anaerobes are heterotrophs, although some do live autotrophically.” 


“Carbon availability for autotrophs, such as cyanobacterium, or those bacteria that utilize light and carbon dioxide to carry out their biological processes and can quickly use an abundance of inorganic carbon.”  


“Heterotrophs are mostly responsible for breaking down organic matter and thrive in areas where diffusion abounds and where organic carbon is well cycled. It is also a fact that mediating biochemical transformations (protein and/or enzymes) and genetic controls (DNA/RNA) show a common reliance on specific ratios of carbon (DOC), nitrogen (DON), and phosphorus (DOP). It could then be said organic carbon is a major player in how well inorganic nutrients, example, nitrogen and phosphorus, are used. In addition, there appears to be a specific ratio needed, which is thought to be approximately 36-parts Carbon, 6-parts nitrogen, and 1-part phosphorus, sometimes referred to as the Redfield Ratio. 

Another thing that pond hobbyists worry about: is that of phosphates. Actually, most phosphates in our ponds are due to food fed and the quality of tap water used for evaporation makeup or water changes. However, it has been said anaerobic areas, were obligate anaerobic heterotrophs live, accumulate phosphates. As a matter fact, the anaerobic area with its lower pH and redox is an efficient user of the oxygen electrons tied to the phosphorus element; therefore, phosphate is quickly reduced to other phosphorus molecules and ions.  

   Therefore, phosphate accumulation anywhere where it is not attacked for its oxygen, suggesting that in more aerobic and anoxic bed areas there would be greater accumulation since oxygen is readily available. However, that is also not accurate! In those areas, it is mostly bound to calcium and manganese (a trace element in Laterite) where it is quite stable because it is very easy to maintain its “charge” balance. Therefore, phosphates are usually not available for uptake in substrates unless associated with reducing conditions.”

Anoxic Filtration Book... Still free on Apple's iBook store

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