Detritus in a reef tank

[Cory]

What makes you believe detritus in our tanks isn't processed many times with fish eating other fishes poo, cuc in the sand, on and in the rocks and corals processing it, protein skimmers; mechanical filtration, chemical filtration, ATS's etc etc ? What I would like to see is some real research into detritus and I struggle to understand why there has not been. I could come up with a few conspiracy theories, however.

Your right it could be processed many times. But most of my detritus is fresh fish poo from what ive seen. My fish dont eat other fish poo. They spit it out. My tanks bb so i see it all, and most accumulates in the sump. The live rock that i have does release detritus from "bacterial tugor". That accumulates in the tank.

That said, in my last tank that was also bb, detritus didnt do anything to algal growth when all the livestock was removed, suggesting its not a sink.

 

[jason2459]

My tangs chase fish they detect pooing trying to get to it

 

[Scott Campbell]

The original post and the article Randy referenced seem to indicate a good portion (most?) of detritus and skimmate are filled with life. Perhaps the problems aquariums experience with detritus are more like the problems associated with bacterial blooms rather than simply an excess accumulation of waste that fuels algae growth. Nano aquariums and newly established aquariums would be more at risk if this were the case. If the detritus communities grow too quickly that could cause oxygen levels to drop and perhaps create other problems for a tank still seeking some state of equilibrium. Rapid algae growth driven by excess nutrients is annoying but I've never felt it was particularly dangerous.

If this were true - then detritus communities, like bacterial communities, might be very worrisome and potentially toxic early in the life of an aquarium. But would likely become an integral and useful component of the tank's microfauna as the tank matured.

 

[Nano sapiens]

The original post and the article Randy referenced seem to indicate a good portion (most?) of detritus and skimmate are filled with life. Perhaps the problems aquariums experience with detritus are more like the problems associated with bacterial blooms rather than simply an excess accumulation of waste that fuels algae growth. Nano aquariums and newly established aquariums would be more at risk if this were the case. If the detritus communities grow too quickly that could cause oxygen levels to drop and perhaps create other problems for a tank still seeking some state of equilibrium. Rapid algae growth driven by excess nutrients is annoying but I've never felt it was particularly dangerous.

If this were true - then detritus communities, like bacterial communities, might be very worrisome and potentially toxic early in the life of an aquarium. But would likely become an integral and useful component of the tank's microfauna as the tank matured.

Detrital communities in most small reef tanks would have some microfauna in the sand bed, but due to the typically high density of fish, crabs, shrimps, etc. predation is high enough to severely limit their numbers (I've looked at various detrital samples from my small 9 year old system under a 10x magnifier and there are relatively few organisms visible under this level of magnification). A much larger system and/or one with much reduced numbers of predators, should have larger populations that would, in theory, keep the substrate more friable.

Substantial algae populations can cause issues for corals both upon physical touching and with the release of DOC (dissolved organic carbon) as a product of photosynthesis. DOC, in quantity, has been shown to literally kill corals as it over stimulates the coral's own microbial community and thus causes coral oxygen starvation.

http://www.cell.com/trends/microbiology/pdf/S0966-842X(10)00133-2.pdf

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0027973

 

[Scott Campbell]

Detrital communities in most small reef tanks would have some microfauna in the sand bed, but due to the typically high density of fish, crabs, shrimps, etc. predation is high enough to severely limit their numbers (I've looked at various detrital samples from my small 9 year old system under a 10x magnifier and there are relatively few organisms visible under this level of magnification). A much larger system and/or one with much reduced numbers of predators, should have larger populations that would, in theory, keep the substrate more friable.

Substantial algae populations can cause issues for corals both upon physical touching and with the release of DOC (dissolved organic carbon) as a product of photosynthesis. DOC, in quantity, has been shown to literally kill corals as it over stimulates the coral's own microbial community and thus causes coral oxygen starvation.

http://www.cell.com/trends/microbiology/pdf/S0966-842X(10)00133-2.pdf

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0027973

Predation of the microfauna doesn't seem particularly linked to the size of an aquarium. Density and type of predators, amount of rock and sand and such would be considerably more relevant. But I'm not sure how much of an impact fish, crabs and shrimp would make if we're mostly talking about bacteria.

I have never noticed substantial algae populations to have the immediate toxic impact that a bacterial bloom can have. Particularly on a small or new tank. No doubt over time algae can have a negative impact. But I usually find other corals to be more toxic to corals than most algae.

If detritus is alive with bacterial life and most of what we skim out of our aquarium is living and/or dead critters, that seems intuitively plausible to me. I've always wondered where all the calcium I keep putting into my tank goes. Might be that I'm skimming a large portion of that calcium back out as microfauna. It also seems plausible that super-charging a detritus bacterial community on a small or new tank would cause problems. While a stable detritus bacterial community on an established tank might be very beneficial.

I honestly have no clue. But it seems genuinely interesting.

 

[Nano sapiens]

Predation of the microfauna doesn't seem particularly linked to the size of an aquarium. Density and type of predators, amount of rock and sand and such would be considerably more relevant. But I'm not sure how much of an impact fish, crabs and shrimp would make if we're mostly talking about bacteria.

I have never noticed substantial algae populations to have the immediate toxic impact that a bacterial bloom can have. Particularly on a small or new tank. No doubt over time algae can have a negative impact. But I usually find other corals to be more toxic to corals than most algae.

If detritus is alive with bacterial life and most of what we skim out of our aquarium is living and/or dead critters, that seems intuitively plausible to me. I've always wondered where all the calcium I keep putting into my tank goes. Might be that I'm skimming a large portion of that calcium back out as microfauna. It also seems plausible that super-charging a detritus bacterial community on a small or new tank would cause problems. While a stable detritus bacterial community on an established tank might be very beneficial.

I honestly have no clue. But it seems genuinely interesting.

Here's how I look at it. Consider a typical small nano tank with 3 or 4 benthic gobies, a Pom-Pom crab and a few hermit crabs. All micro predators or predator/scavengers living in a small confined area preying on small macro and large micro fauna. In a much larger tank, the ratio of substrate suitable for these small food organisms is typically greater in relation to the large macro fauna and the predators tend to be of the larger type which would be more interested in larger food stuffs (exceptions of course if one has large sand sifters or a large tank full of small micro predators). I guess until someone legitimately tests this out, it's just a theory (as are many things in this hobby)

The substrate and detritus is undoubtedly full of bacteria, protists, archaea, etc. and are what make detritus nutritious for filter feeders. Undoubtedly, some of the calcium is removed via skimming and I believe that some is incorporated into the biologically-induced mineralization process (I used to wonder how all that 'sand' gets into my rear chambers every week).

Interesting question regarding the super-charging of a detritus bacterial community. Typically, what happens in a newly set up system is that the right types of bacteria, in balanced ratios to carry out the various cycles effectively, are not yet established. If one were to add the correct type and numbers of these various bacteria, that should be helpful. I'd imagine that adding a very large dose of bacteria all-at-once to such a new system could lead to a decrease in oxygen from the decomposition of any excess bacteria...plus degradation of the water quality.

 

[Cory]

Im sure poo isnt healthy in such a small body of water. Close up your house, circulate the air (no outside air) and poo in the corner for a few year. Oh and dont go outside either. Whats going to happen? Probably your going to get very sick. Ive seen detrtus accumalte in my overflow and made some of my fish get bacterial infections. This detrtus was dark brown. No matter how you look at it, its not healthy. Imo.

 

[atoll]

Im sure poo isnt healthy in such a small body of water. Close up your house, circulate the air (no outside air) and poo in the corner for a few year. Oh and dont go outside either. Whats going to happen? Probably your going to get very sick. Ive seen detrtus accumalte in my overflow and made some of my fish get bacterial infections. This detrtus was dark brown. No matter how you look at it, its not healthy. Imo.

But tanks are receiving oxygen from the outside, poo is being consumed etc etc, no comparison sorry your way off with that analogy.

 

[Paul B]

I love detritus. If your tank is old enough and natural enough it will house thousands or millions of tiny creatures, mostly tube worms that live on that stuff. I run a reverse UG filter and I never see any detritus in my tank. None at all. I change little water and stir the gravel once a year just so it doesn't clog. Those tube worms I assume filter the water maybe turning it completely over once a day. My tank is crystal clear and if I look real close, I can see all those tube worms smiling. I feed a lot of natural foods like clams which exude a milky substance which those creatures go nuts for. They would do back flips but their tails being cemented to the bottom prevent that.
I recently had to remove my UG filter tubes to chop out the tube worms that clogged the thing. I see that as a good thing as life of any type in a reef tank is good. They even live in my skimmer which is weird because the thing is always filled with Ozone.
(Maybe that's why deep sea tube worms can live in sulfur filled water that is exuded from volcanic vents at the bottom of the sea.)
If your tank is not natural, not old enough or of you don't feed enough, you will not have those and the detritus will be noticeable all over the place.
Just my opinion and the opinion of my tube worms.

 

[Scott Campbell]

Im sure poo isnt healthy in such a small body of water. Close up your house, circulate the air (no outside air) and poo in the corner for a few year. Oh and dont go outside either. Whats going to happen? Probably your going to get very sick. Ive seen detrtus accumalte in my overflow and made some of my fish get bacterial infections. This detrtus was dark brown. No matter how you look at it, its not healthy. Imo.

Cory - I think you are correct and I think your analogy is instructive. If you manage an aquarium like a house, there really is no effective means of processing waste (assuming you poop in a corner of the house and don't use the toilet). There will be flies and god knows what - but the poop is going to accumulate and soon pose a health hazard. But if you poop outdoors, it is a whole different ballgame. Poop does not pose a health hazard outside. Quite the opposite.

So if you run a bare bottom tank and siphon out detritus on a regular basis and largely limit microfauna growth - then you have created a tank that mimics a house environment. Which is of course fine. You will simply need to continue to siphon out the detritus. But if you run an "outdoors tank" like Paul B, that detritus is no longer a problem.

 

[Nano sapiens]

The way I look at it...

For those like Paul with very old, established tanks, his method of once a year flushing/polishing mimics a powerful storm that would seasonally occur in nature. For others that remove detritus regularly (substrate stirring/vacuuming, live rock 'basting'), the method is perhaps more similar to a series of multiple 'mini storms'. The end effect is similar in that the substrate is cleared of choking amounts of detritus, which then allows the benthic microfauna to work efficiently to keep the system in good shape.

 

[atoll]

People seem to be forgetting just what animals and bacteria are in the sand and detritus and are almost dismissing it. Like Paul I have multitudes of animals some microscopic others like cucumbers and snails all living off what is in my sand. Now guess what that might be and its burgers and fries. There is a lot of recycling going on in there and we could learn a lot from mother nature when it comes to processing and recycling and very little is wasted IMO.

 

[klp]

Got an answer back from Marineland that you can also use their external canister filters as well. You just have to pre-charge them as you do the Vortex. I also asked if the micropads would do the job. Negatory good buddy. Their comment is below:
Yes, you can add diatomaceous earth to the system by pouring it into a container, and setting the intake and outlet tubes in the container. The polishing pads are made from a material that does not have a micron rating corresponding to ppi.

 

[Cory]

But tanks are receiving oxygen from the outside, poo is being consumed etc etc, no comparison sorry your way off with that analogy.

Water would be air in the house.

The ocean doesnt compare to a tank. Detritus gets swept away into the deep. And that water get processed a lot before it reaches the coral reef. Sand near a reef shouldnt be loaded with fresh poo. Maybe its loaded with seagrass, but any decaying seagrass is accompained by a huge amount of water bringing in the cleaner water.

If you were to minick the sea in a tank, you need something like 1 million gallons of water. Its pretty hard to do, so i think its better to get the poo and uneaten food out before it rots. All just imo.

 

[BluewaterLa]

Water would be air in the house.

The ocean doesnt compare to a tank. Detritus gets swept away into the deep. And that water get processed a lot before it reaches the coral reef. Sand near a reef shouldnt be loaded with fresh poo. Maybe its loaded with seagrass, but any decaying seagrass is accompained by a huge amount of water bringing in the cleaner water.

If you were to minick the sea in a tank, you need something like 1 million gallons of water. Its pretty hard to do, so i think its better to get the poo and uneaten food out before it rots. All just imo.

From visiting a few reefs and lagoons I can tell you that there is a large amount of detritus and decaying matter to be found in these areas, though its not as in your face as some see in their tiny glass boxes at home it still none the less is a natural component in mother natures tank.
While a vast majority of it is indeed eventually settled out into the deep to be on day turned into magma, the reefs thrive off of detritus and flock as the many organisms found on all different levels either directly utilize it or help create it.

 

[xjiang7]

don't forget the organics made by photosynthesis

 

[jason2459]

Detritus is

Water would be air in the house.

The ocean doesnt compare to a tank. Detritus gets swept away into the deep. And that water get processed a lot before it reaches the coral reef. Sand near a reef shouldnt be loaded with fresh poo. Maybe its loaded with seagrass, but any decaying seagrass is accompained by a huge amount of water bringing in the cleaner water.

If you were to minick the sea in a tank, you need something like 1 million gallons of water. Its pretty hard to do, so i think its better to get the poo and uneaten food out before it rots. All just imo.

Detritus is everywhere. It does not get swept away to the depths. Growing up and studying the ecosystem around south Florida ocean and bay sides it is based off detritus. Best snorkeling is right along mangrove islands. Filled with detritus and life of all kinds.

Also, where do you think all the sand came from? Go swimming around the reefs. Watch those beautiful looking parrot fish.

Check out how much algae growth there is when the herbivor population tanks or is very low in places. Take a boat ride scoping out new small reefs reefs. Look for brown spots among the green.

And no I don't think we can mimic the oceans in our very small boxes. Even the ones we think are large. But biodiversity is good how ever you want to achieve it.

 

[Paul B]

Detritus is everywhere. It does not get swept away to the depths. Growing up and studying the ecosystem around south Florida ocean and bay sides it is based off detritus. Best snorkeling is right along mangrove islands. Filled with detritus and life of all kinds.

That is correct. I took this off a mangrove Island there. It's all detritus. If it were not for detritus, there would not be this abundance of fish there or anywhere

 

[atoll]

Nobody is suggesting our glass boxes are exactly like the reef of which there are many different types of reefs. Everything we do is a compromise no matter if it is lighting or filtration and IMO detritus and its export (or not) is similar. Pick a rock up off the sand on a reef (as I have done in the Red sea) and you will find detritus along with various life forms.

 

[Cory]

You guys are thinking your tanks are coral reefs. They lack the whole ocean and its dynamics. There is very little similar to a reef in a fish tank. Think bigger. Theres a lot more going on than just a coral reef in the sea, its all connected. Nothing comes in and nothing comes out. Fish tanks lack a lot of fuctions of the sea. The abyss is one but one example. There are many.

The animals you want to keep dont really live in a magrove swamp. If they did theyd die pretty quickly by sedimentation. Just condider that for a second, then think how your tank works.

You constantly put food in your tank. The ocean and coral reef doesnt have input. Its an ecosystem based on what's available, and thats why we have them. A coral reef exists on what very little is available, and they live in a nutrient dessert. What happens when you keep adding food to a tank? What would happen to the sea? The point is detrtus is okay if you can mimick the sea, but you cant. Eventually sandbeds get full of organics and your tank will become eutrophic, and no longer trophic. Imo