Detritus Food Web

[NaH2O]

I had no idea there was a separate food web for detritus? So, what exactly is detritus composed of (material from dead organisms, is all I could find...material like what?) - who/what produces detritus, and which organisms bring the detritus food web into the grazing food web (talking marine environments)? Also, in a closed system, does the detritus food web differ or lack anything compared to the ocean environment?

 

[wrightme43]

It is my understanding that bacteria live on it and thru it. I think that they secrete enzymes that break it down in to other things they can use and other bacteria work on thier waste products or reduction products. I believe the corals, amemone, clams and some snails eat this stuff and use it for energy to grow. Just my understanding and I am not always right. Steve

 

[MikeS]

I've always worked under the definition of detritus as being all the solid organic matter being processed biologically in the tank...ie fish waste, decaying matter of any kind like leftover food, ect...

I would think the web would include any critter that aids in this process, like pods, worms, bacteria, ect.

MikeS

 

[mojoreef]

Steve your pretty much dead on.

Mike that iskind of the way I look at it to. Nikki detritus is a portion of an overall food web. What did you find??


Mike

 

[NaH2O]

Where do bacterias enter the detritus food web? At the break down of detritus? Steve, this may be why the understanding of detritus having bacteria living on it and through it. So, if detritus is simply organic matter of wates and decaying matter, then it is primary in grazing food webs....because other organisms feed on the bacterias that feed on detritus. This would then create more detritus, etc etc. Would there always be a balance in the web, or in closed systems are we skewed too far in detritus production vs. removal?

 

[mojoreef]

Oh man your on a roll this morning, hehehe. Most organisms feed on the detritus also and get the benefit of the bacteria and all the other critters associated with it. This is why I push folks not to feed so much to thier tank as the detritus is a constant source and a viable one. On the balance thats a tougher question and really has to do with the persons husbandry. I would say in 99% of the cases though that more detritus will be added then removed the reasoning behind a good skimmer and syphoning.


Mike

 

[MikeS]

I agree....but I'd add that probably the largest single factor in that equation is how much solid organics (food) are introduced into the system in the first place.

MikeS

 

[VINA DEL MAR]

I believe that SPS corals also feeds on the bacteria that lives in detritus,right?And then the corals again produces more detritus and the cycle continuous all over again.
Man that what I call recycling.LOL

VINA

 

[NaH2O]

Sorry Mike/mojo - I must have posted at the same time as you this morning, so I didn't see your first post until now. I was trying to get an understanding of the basis of food webs last night. I always assumed, I guess, that phytoplankton kind of fueled everything, but never even thought smaller than that. My brain is very tired right now, so I'll refrain from putting a decent thought together. I looked at this as showing me no matter what kind of filtration - there will always be some available to keep everyone fed. Would there really be a need to dose phytoplankton (for those that do) to a system, if you allow some DOM and POM to remain in the water? This diagram took forever (below is the explaination of it).... I don't have a scanner, so this is the best I could do to explain what I found.

Conceptualization of the overall microbial food web, redrawn from the diagram of Sherr and Sherr (1988), based on information gained since the early 1980s. Black arrows show pathways of consumption of organic matter; red arrows show pathways by which organic matter, both dissolved (DOM) and particulate (POM) is released from living organisms. The microbial food web is divided between autotrophic and heterotrohic microbes. Autotrophs are further separated into cells greater than 5µm in size, which are large enough to be grazed by copepods and other multicellular zooplankton, and cells smaller than 5µm, which are mainly consumed by protists. Zooplankton feed not only on the larger phytoplankton but also on bacterivorous protists (nanoflagellates and smaller ciliates) and on herbivorous protisis (larger nanoflagellates, heterotrophic dinoflagellates, and ciliates). Three new pathways - mixotrophic consumption of bacteria by phytoflagellates, viral lysis of bacteria, and uptake of high molecular weight DOM by bacterivorous protisis - are shown as well.

This is from Microbial Ecology of the Oceans.

 

[wrightme43]

Yeah What Nikki said. LOL Uhhhhhhhhh. Corals eat coral poop. After it is eatin by other stuff, and Light adds energy that is made into food/poop that is made into energy/food/poop. LOL Sorry I just couldnt help myself. LOL Steve

 

[mojoreef]

Vina you will find that corals dont give up much waste/biproduct if any, thier a pretty stingy breed, lol.

Nikki the diagram is more of what happens in the wild. In the deeper open ocean thier are alot of ammonium upwellings, this is where the phyptoplankton really bloom, then they drift over the reef where they are consumed. In a reef tank this doesnt happen (well rarely anyway). But that bottom end of the cycle still pertains and is even magnified.


Mike

 

[DonW]

I wonder if our tank inhabitants are picky about what fish poop they eat. Does what we feed our fish affect the health of other critters. For example are SPS more fond of Tang poop because we tend to feed them alot of nori.

Don

 

[NaH2O]

Good question, Don. I wonder if it has more to do with the species of coral you are talking about. Would one type of coral favor the bacteria present in waste over the actual waste?

 

[DonW]

Good question, Don. I wonder if it has more to do with the species of coral you are talking about. Would one type of coral favor the bacteria present in waste over the actual waste?

I'm sure thats pretty much the case with soft corals. I know some have to have a good supply of bacteria.
I do question wether or not feeding fresh/frozen vs freeze dried foods has any effect on sps.

Don

 

[mojoreef]

Don I think SPS would take fresh food or possibly even dried if it were the right size. The concept is that thier is already more then enough detrital/plantonic food in the tank already, so feeding just for them just adds to the nutrient load you have to deal with.

Nikki the coral will take what it needs and pass on to the zoox the balance in most cases.

Mike

 

[jeffkeith_us]

Vina you will find that corals dont give up much waste/biproduct if any, thier a pretty stingy breed, lol.

Nikki the diagram is more of what happens in the wild. In the deeper open ocean thier are alot of ammonium upwellings, this is where the phyptoplankton really bloom, then they drift over the reef where they are consumed. In a reef tank this doesnt happen (well rarely anyway). But that bottom end of the cycle still pertains and is even magnified.


Mike

Every so often I feed my aquariums till I get an ammonium spike. Right at or just after the 420 and 460 nm lamps are turned off by the timer. Not all at once but over a weekend till I get an alge bloom. Each night I feed just enough to get the amphipods to increase their population.
I started doing that after I left a dead snail in #4 just to see what would hapen. First an alge bloom, then copepods, and then amphipods. At that time #4 had two E. quadracolor anemone, but no fish. The ammonia didn't bother anything. I think ammonium upwelling in the sea work just like a rain storm for us.
Jeff