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Unread 01/07/2018, 03:15 PM   #56
Dan_P
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Join Date: Aug 2014
Posts: 1,432
Quote:
Originally Posted by Belgian Anthias View Post
All data is available as heterotrophic ammonia and nitrate reduction has been researched thoroughly during past decennia in university's all over the world. I have used research of Ebeling, J.M., Timmons, M.B., Bisogni, J.J., 2006. (Engineering analysis of the stoichiometry of photoautotrophic, autotrophic, and heterotrophic removal of ammonia–nitrogen in aquaculture systems. Aquaculture 257, 346–358. https://doi.org/10.1016/j.aquaculture.2006.03.019)
to help develop my point of view. The publication can be consulted http://www.baharini.eu/baharini/doku...onium_reductie
Yes this is good read if you want to know about the science behind carbon dosing but a somewhat more readable version was presented at the 6th International Conference on Recirculating Aquaculture. It is published here.

https://ejournals.lib.vt.edu/ijra/ar...view/1336/1814

Figure 2 is important to put the ideas in this post in perspective. The bar chart reflects Jonathan’s perspective. Unless the C:N ratio is very high, you always have some autotrophic activity. Ending carbon dosing suddenly when the system is heavily dependent on heterotrophic activity to remove nitrogen seems likely to produce an ammonia spike, but you haven’t provided evidence or calculated a C:N ratio for a typical aquarium to show whether the typical aquarium heterotrophic:autotrophic ratio is on the edge of disaster. The notion to use care tapering off carbon dosing is sound advice. Whether a sudden cessation is dangerous has yet to be demonstrated.

Where I think we missed an important point in this discussion is that the ratio of heterotrophic:autotrophic may be predictive of a system’s propensity to grow nuisance photoautotrophs such as diatoms, dinoflagellates, cyanobacteria and algae. The notion that nitrate and phosphate are predictive or are the cause of nuisance organism growth needs to be revisited. It might be more useful to think in terms of inadequate heterotrophic activity or a low C:N ratio as the cause of nuisance organism growth.


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