Dear all
The question of the day from Friday: UV Sterilizers: Are the benefits a MYTH or a REALITY?, as turned out to be a very interesting topic with lots of different experiences.
However, I was wondering, for those that use UVs, have you been able to disconnect them without having issues? Or do you find that when disconnecting them problems arise?
The idea here is not to get into the discussion of whether UVs work or not, you can do that at the Friday topic (link below). Just simple, can you turn your UVs off without a problem?
www.reef2reef.com
My question stems from my professional work. I do research in recirculation aquaculture.
In ecology there is a theory of R/K strategies in relation to bacteria growth. R bacteria are fast growers and generally opportunistic, while K strategists are slow growers. A typical example of K strategists are nitrifying bacteria. There are probably some ecologists in the forum that can explain this better then I can.
In my field of work it is one of the research fields and mentalities, that disinfection should not be used to allow slow growing bacteria (K strategy) to develop and take over. If the system is stable the bacteria will fill up all the systems carrying capacity (the systems maximum sustainable biomass) and will not allow bacteria with potential negative effects to take hold.
If you use a UV you will kill both bacteria, but since R strategist multiply must faster they can take a much faster hold and take over the system, creating a problem, if not controlled.
In marine larvae systems this has been shown to produce good results (articles below).
One thing that UVs do is transfer organic matter from the water column to fixed media (at least in RAS) by killing the bacteria in the water phase. Therefore, all organic matter that would normally be bound in their biomass is available for other organisms to use (normally the ones that will not come in contact with the UVs).
Now, bear in mind that this comes from the world of research and commercial aquaculture, where organic loads are much higher. However, from a stability point of view, our systems should be much more effective at this.
Thank you all for participating.
Literature
R/K strategy
The Theory of Island Biogeography
R.H. MacArthur, E.O. Wilson
Princeton University Press, Princeton, NJ (1967)
Google Scholar
A strategy to obtain microbial control during larval development of marine fish
O. Vadstein, G. Øie, Y. Olsen, I. Salvesen, J. Skjermo, G. Skjåk-Bræk H. Reinertsen, L.A. Dahle, L. Jørgensen, K. Tvinnereim (Eds.), Proceedings of the First International Conference on Fish Farming Technology, Trondheim, Norway, 9–12 August 1993. Balkema, Rotterdam (1993), pp. 69-75
Google Scholar
Effects on marine larvae rearing
Recirculation as a possible microbial control strategy in the production of marine larvae.
Attramadal, K.J.K., Salvesen, I., Xue, R., Øie, G., Størseth, T.R., Vadstein, O., Olsen, Y., 2012a. Aquac. Eng. 46, 27–39. https://doi.org/10.1016/j.aquaeng.2011.10. 003.
The effects of moderate ozonation or high intensity UV-irradiation on the microbial environment in RAS for marine larvae.
Attramadal, K.J.K., Øie, G., Størseth, T.R., Alver, M.O., Vadstein, O., Olsen, Y., 2012b. Aquaculture 330–333, 121–129. https://doi. org/10.1016/j.aquaculture.2011.11.042.
Transfer of organic matter
UV irradiation and micro filtration effects on micro particle development and microbial water quality in recirculation aquaculture systems
de Jesus Gregersen, K.J., Pedersen, P.B., Pedersen, L.-F., Liu, D., Dalsgaard, J.
(2020) Aquaculture, 518, art. no. 734785.
http://www.journals.elsevier.com/aquaculture/
doi: 10.1016/j.aquaculture.2019.734785
The question of the day from Friday: UV Sterilizers: Are the benefits a MYTH or a REALITY?, as turned out to be a very interesting topic with lots of different experiences.
However, I was wondering, for those that use UVs, have you been able to disconnect them without having issues? Or do you find that when disconnecting them problems arise?
The idea here is not to get into the discussion of whether UVs work or not, you can do that at the Friday topic (link below). Just simple, can you turn your UVs off without a problem?
QUESTION OF THE DAY - UV Sterilizers: Are the benefits a MYTH or a REALITY?
UV Sterilizers: Are the benefits a MYTH or a REALITY? Let's talk a hot button topic today. Let's talk about UV sterilizers and if you believe the benefits of running one on your aquarium system is a myth or reality! Here is a description I found for UV sterilizers. How UV Works? Ultraviolet...
www.reef2reef.com
My question stems from my professional work. I do research in recirculation aquaculture.
In ecology there is a theory of R/K strategies in relation to bacteria growth. R bacteria are fast growers and generally opportunistic, while K strategists are slow growers. A typical example of K strategists are nitrifying bacteria. There are probably some ecologists in the forum that can explain this better then I can.
In my field of work it is one of the research fields and mentalities, that disinfection should not be used to allow slow growing bacteria (K strategy) to develop and take over. If the system is stable the bacteria will fill up all the systems carrying capacity (the systems maximum sustainable biomass) and will not allow bacteria with potential negative effects to take hold.
If you use a UV you will kill both bacteria, but since R strategist multiply must faster they can take a much faster hold and take over the system, creating a problem, if not controlled.
In marine larvae systems this has been shown to produce good results (articles below).
One thing that UVs do is transfer organic matter from the water column to fixed media (at least in RAS) by killing the bacteria in the water phase. Therefore, all organic matter that would normally be bound in their biomass is available for other organisms to use (normally the ones that will not come in contact with the UVs).
Now, bear in mind that this comes from the world of research and commercial aquaculture, where organic loads are much higher. However, from a stability point of view, our systems should be much more effective at this.
Thank you all for participating.
Literature
R/K strategy
The Theory of Island Biogeography
R.H. MacArthur, E.O. Wilson
Princeton University Press, Princeton, NJ (1967)
Google Scholar
A strategy to obtain microbial control during larval development of marine fish
O. Vadstein, G. Øie, Y. Olsen, I. Salvesen, J. Skjermo, G. Skjåk-Bræk H. Reinertsen, L.A. Dahle, L. Jørgensen, K. Tvinnereim (Eds.), Proceedings of the First International Conference on Fish Farming Technology, Trondheim, Norway, 9–12 August 1993. Balkema, Rotterdam (1993), pp. 69-75
Google Scholar
Effects on marine larvae rearing
Recirculation as a possible microbial control strategy in the production of marine larvae.
Attramadal, K.J.K., Salvesen, I., Xue, R., Øie, G., Størseth, T.R., Vadstein, O., Olsen, Y., 2012a. Aquac. Eng. 46, 27–39. https://doi.org/10.1016/j.aquaeng.2011.10. 003.
The effects of moderate ozonation or high intensity UV-irradiation on the microbial environment in RAS for marine larvae.
Attramadal, K.J.K., Øie, G., Størseth, T.R., Alver, M.O., Vadstein, O., Olsen, Y., 2012b. Aquaculture 330–333, 121–129. https://doi. org/10.1016/j.aquaculture.2011.11.042.
Transfer of organic matter
UV irradiation and micro filtration effects on micro particle development and microbial water quality in recirculation aquaculture systems
de Jesus Gregersen, K.J., Pedersen, P.B., Pedersen, L.-F., Liu, D., Dalsgaard, J.
(2020) Aquaculture, 518, art. no. 734785.
http://www.journals.elsevier.com/aquaculture/
doi: 10.1016/j.aquaculture.2019.734785
