Why Fish in Captivity get Sick



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Jun 21, 2018
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@Paul B
I recently started a thread about biofilms on macro surfaces. In doing some research on intensive mariculture, I find that biofilm is at the heart of nutrition regime.

For certain I still feed live bivalves, however I thought that smart bacteria could be part of a healthy diet along with gut bacteria.

With respect to our reef tanks, this stuff sounds like nutrition on steroids and a little bit of Avatar:
Quorum sensing molecules/bioactive molecules that protect host against harmful entities. Considering the holistic nature of the Coral Holobiont I have always embraced biology over technology. With this scientific paper we are told that biochemistry is so much more complicated than “rocket science” that it takes multi disciplines of science (ecological, microbial and biochemical) to understand the “intelligent design” of one part of Coral Holobiont.

[Bacterial communities belonging to the phyla Proteobacteria and Firmicutes are generally the most abundant on seaweed surfaces. Associated bacterial communities produce plant growth-promoting substances, quorum sensing signalling molecules, bioactive compounds and other effective molecules that are responsible for normal morphology, development and growth of seaweeds. Also, bioactive molecules of associated bacteria determine the presence of other bacterial strains on seaweeds and protect the host from harmful entities present in the pelagic realm. The ecological functions of cross-domain signalling between seaweeds and bacteria have been reported as liberation of carpospores in the red seaweeds and settlement of zoospores in the green seaweeds. In the present review, the role of extracellular polymeric substances in growth and settlement of seaweeds spores is also highlighted. To elucidate the functional roles of associated bacteria and the molecular mechanisms underlying reported ecological phenomena in seaweeds requires a combined ecological, microbiological and biochemical approach.]
RAP Orlando
Paul B

Paul B

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The seaweed surface provides a suitable substratum for the settlement of microorgansims and also secretes various organic substances that function as nutrients for multiplication of bacteria and the formation of microbial biofilms (Steinberg et al., 2002; Staufenberger et al., 2008; Singh, 2013). Microbial communities living on the seaweed surface are highly complex, dynamic and consist of a consortium of microorganisms including bacteria, fungi, diatoms, protozoa, spores and larvae of marine invertebrates

This is also the reason new ASW is a lousy substitute for real seawater. It takes a long time for these things to form in a home tank, if they ever form using ASW. In any case, they won't be present right away but may begin to accumulate if we allow algae to grow in our systems.

How important is sand sifting or sand stirring livestock to your reef tank?

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  • Somewhat important

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  • Other (please explain)

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