Live Rock...Is there a point??
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ricanreefer
New member
i have a 65 g with no filtration and do little water changes and thw tank and fish and polys are fine live rock is my filter so it works for me
sparkey_burke
In Memoriam
live rock is a very important part of any reef system
G-money
Premium Member
Philosophical differences, Chris. It must be - because we both disagree with about everything the other has to say. Allow me to reiterate that I use live rock...but my tank is not a worm farm - and never will be.
<a href=showthread.php?s=&postid=7126652#post7126652 target=_blank>Originally posted</a> by MCsaxmaster
How do you mean complete? Single phytoplankter species as producer and a single bacterial species as decomposer is a food web (chain in this case).
Nope. Not as far as completeness is considered. Does the fact that a bacteria can feed on a dead phyto cell make it a food chain? This is the "nature" we're after in our tanks? This is the system that's going to keep my tank low in nutrients? No, it's the niches in between that should concern us just as much. If a food web is what we're after...and I'm not. If I have an organism that is only able to feed on a certain size of detrital element(s) passed down from an organism "above it", what happens if that organism providing the food has its extinction? Basically this will eventually happen in any closed system. Now am I going to worry about whether all my niches are still intact in 5 years, or am I going to take care of it myself? The answer is B.
You don't want anything in the tank to grow?
No Chris, a food web has all trophic levels from primary producers to decomposers. Our tanks are not food webs because we put in and we take out. The system does not maintain itself, even if you have the healthiest sandbed and live rock in the universe. It never will and that's the reality of it. That's a bitter pill for the "natural reef tank lover" to swallow.
Sure. So have live rock and a sand bed and one fewer fish; problem solved.
Nah, sanbeds are nutrient sinks. There are much better approaches IMO.
More later....duty calls.
G-money
Premium Member
<a href=showthread.php?s=&postid=7126652#post7126652 target=_blank>Originally posted</a> by MCsaxmaster
Reverse lighted refugiums are probably a good idea no matter what is in the tank.
Not in every system. I can't keep any macro other than halimeda growing in my tank for any period of time. Chaeto I've tried twice since going "low nutrient" and it just doesn't grow. It used to grow just fine when I ran a "dirtier" system.
As for the sand becoming anoxic, 1. why is that happening in shallow sand, or 2. if it's only happening in deeper levels of sand that's normal, and why should I care?Most sand and mud animals live in anoxic sediment. That's normal. It seems that most reef tanks have relatively higher O2 content in the sand (judging from a RK article from a bit ago), so why should that make us worry? As for species going extinct, there's no way to prevent that really. Reintroductions of new sand and/or rock every year or few years is probably a good idea. A lot of areas in nature tend to be patchy though, and there is probably overlap in the effective niche of most species. So while reef-like biodiversity is desirable, less than that is still quite functional.
Other than bacteria, not much is going to thrive in anoxic sediments. Anoxic is something I try to avoid in my "non-natural" system (other than live rock). Even with that, there is no nitrate testable in my system. Live rock is plenty for that as long as you don't sink your waste. If your power went out, your sand would be the first thing to become depleted in O2. I've experienced longer-term (4-6 hours) power outages and it destroyed my sandbed life - while the rest of the system was largely unharmed.
I don't want these types of things happening in my tank to a large degree. This isn't really about live rock, though so I'll drop it.
Why is this less under ones control? Most infauna are incredibly hardy anyway. Actions that will kill them in good numbers are probably wreaking havoc on everything else in the tank first (minus maybe treatments with things like flea-pills). I mean, should we all be worried when are corals grow larger that the larger biomass is going to be detrimental to the tank somehow? Lots of nutrients in that coral tissue and skeleton. I disagree. Do I want nutrients controlled by organisms or by my own volition? Again, I'll take the responsibility.
Short of blasting down the tank and doing large water changes frequently, how are you going to ever maintain dissolved nutrients levels anywhere near natural levels? Without a lot of creatures actively consuming waste it will just be broken down by heterotrophic bacteria (no way to eliminate them but to sterilize the tank, which would kill anything we want to keep in it). Almost nothing is happening in our tanks that isn't directly mediated biologically.
Bacteria are fine. That's what I want to control these things, but that's it. I can skim aggressively, use UV to kill bacteria, skim them as well...Wet skimming removes particulate matter very well. If you let nutrient matter sit and breakdown in your tank, then yes, it is being mediated 100% biologically. I don't do that, though.
Our technology just simply can't provide most of the functions that reefs and adjacent habitats provide.
Such as? Give me an example.
Ok. Again, what are you considering "incomplete?" Biodiversity improves the efficiency of resource usage, but so far as is known (really, really hard to do these studies) it probably doesn't take a lot in most cases. Often the apparent "extra" biodiversity provides system stability through overlap in the effective niches of species.
Biodiversity adds waste. Plain and simple. Nothing gets completely elimiated biologically. It just changes form as we know. With that, it's either recycled or it accumulates in biomass and sediiments. I want it out because I can't provide the ecosystem to deal with it naturally. Some choose to grow populations of organisms and boom/bust. That's uncontrolled - what grows, what dies, etc.
That's not the way I want to approach my tank.
The whole point of fishkeeping to me is to take a part of nature and re-create it in a box so that i can enjoy it every day. For me every extra thing people slap onto their tanks takes away from that. For the nano tank im about to set up im hoping to go with almost entirely natural filtration, i think that will make the tank much more realistic. Live rock is necessary because it provides very large surface areas for the breakdown and conversion of chemicals, weather the rock has been taken from a reef or made out of pipe and cement doesnt really matter. Bragging that you 12' high 4' wide Ã"šÃ‚£5000 skimmer can take care of all your filtration is great but again i think that detracts fro the fact we are all trying to recreate a part of the ocean in our own homes. Personally i feel that a tank that can sustain itself is the ultimate goal of fishkeeping, creating environments that are self sustaining and i think when we talk about reef keeping live rock is an essentail part of that.
MCsaxmaster
New member
Not in every system. I can't keep any macro other than halimeda growing in my tank for any period of time. Chaeto I've tried twice since going "low nutrient" and it just doesn't grow. It used to grow just fine when I ran a "dirtier" system.
If that's your definition of "dirty" then coral reefs in nature are horrendously "dirty." Macroalgae and turf algae grow like crazy as soon as substrate is caged so herbivores can't get in. If macroalgae won't grow in your system when the herbivores are kept away from it then it is a not a very accurate representation of a coral reef.
Other than bacteria, not much is going to thrive in anoxic sediments. Anoxic is something I try to avoid in my "non-natural" system (other than live rock). Even with that, there is no nitrate testable in my system. Live rock is plenty for that as long as you don't sink your waste. If your power went out, your sand would be the first thing to become depleted in O2. I've experienced longer-term (4-6 hours) power outages and it destroyed my sandbed life - while the rest of the system was largely unharmed.
Well, I'm not sure how to say this nicely, but you're just plain wrong. Almost all of the mud, sand, and other soft sediment in the world (rivers, lakes, estuaries, mangroves, seagrass beds, etc.) is anoxic within milimeters of the surface. Areas of lower decomposition are anoxic within centimeters of the surface. A huge diversity of life, not to mention a large physical biota, lives in totally anoxic sediments. Anoxic sediments is normal, not unusual. I will also note that in post particles of detritus and certainly any nook or crany of the tank there are anoxic spots. That's just the nature of, well, nature.
I want nutrients controlled by organisms or by my own volition? Again, I'll take the responsibility. The amount of biomass contributed by even a large (for a tank) Acropora is miniscule. Probably as much as single large worm. Corals also have a more "tidy" way of taking care of waste than worms and crustaceans.
Well, I would suggest that the animals are the tools at ones disposal. I'm not sure how one would accomplish many of the tasks done easily in a biodiverse tank, such as feeding heavily with little export of waste, and thus little effort, or feeding of various planktonic organisms. Certainly corals can be kept alive and grown without these things, but I've yet to see what I would consider the same level of success with many organisms without a great deal more husbandry in biodiverse vs. relatively sterile tanks.
Bacteria are fine. That's what I want to control these things, but that's it. I can skim aggressively, use UV to kill bacteria, skim them as well...Wet skimming removes particulate matter very well. If you let nutrient matter sit and breakdown in your tank, then yes, it is being mediated 100% biologically. I don't do that, though.
Ok?
Such as? Give me an example.
e.g. The production of most any type of planktonic food, especially below about 10 um. Nitrification-denitrification biofilms.
Biodiversity adds waste. Plain and simple.
Again, not to be rude, but flat wrong. Biodiversity diminishes waste, and that has been proven experimentally.
Nothing gets completely elimiated biologically. It just changes form as we know. With that, it's either recycled or it accumulates in biomass and sediiments. I want it out because I can't provide the ecosystem to deal with it naturally. Some choose to grow populations of organisms and boom/bust. That's uncontrolled - what grows, what dies, etc.
Ok, certainly not trying to tell you how to run your tank, but far and away the easiest to run and what I would consider the most successful tanks are those that had a decent helping of diversity including a lot of meiofauna and infauna. The diversity and quality of the planktonic food produced in these tanks seems to be so much better than what we can provide right now. These tanks just seem to have the fewest problems too. Of course this is very objective, but it just seems like everything works in these tanks. The fish eat and are healthy. The corals grow. The skimmer skims. Everything just runs smoothly. I've not seen this sort of smooth operation without a lot more labor in more sterile tanks, but hey, who knows?
cj
If that's your definition of "dirty" then coral reefs in nature are horrendously "dirty." Macroalgae and turf algae grow like crazy as soon as substrate is caged so herbivores can't get in. If macroalgae won't grow in your system when the herbivores are kept away from it then it is a not a very accurate representation of a coral reef.
Other than bacteria, not much is going to thrive in anoxic sediments. Anoxic is something I try to avoid in my "non-natural" system (other than live rock). Even with that, there is no nitrate testable in my system. Live rock is plenty for that as long as you don't sink your waste. If your power went out, your sand would be the first thing to become depleted in O2. I've experienced longer-term (4-6 hours) power outages and it destroyed my sandbed life - while the rest of the system was largely unharmed.
Well, I'm not sure how to say this nicely, but you're just plain wrong. Almost all of the mud, sand, and other soft sediment in the world (rivers, lakes, estuaries, mangroves, seagrass beds, etc.) is anoxic within milimeters of the surface. Areas of lower decomposition are anoxic within centimeters of the surface. A huge diversity of life, not to mention a large physical biota, lives in totally anoxic sediments. Anoxic sediments is normal, not unusual. I will also note that in post particles of detritus and certainly any nook or crany of the tank there are anoxic spots. That's just the nature of, well, nature.
I want nutrients controlled by organisms or by my own volition? Again, I'll take the responsibility. The amount of biomass contributed by even a large (for a tank) Acropora is miniscule. Probably as much as single large worm. Corals also have a more "tidy" way of taking care of waste than worms and crustaceans.
Well, I would suggest that the animals are the tools at ones disposal. I'm not sure how one would accomplish many of the tasks done easily in a biodiverse tank, such as feeding heavily with little export of waste, and thus little effort, or feeding of various planktonic organisms. Certainly corals can be kept alive and grown without these things, but I've yet to see what I would consider the same level of success with many organisms without a great deal more husbandry in biodiverse vs. relatively sterile tanks.
Bacteria are fine. That's what I want to control these things, but that's it. I can skim aggressively, use UV to kill bacteria, skim them as well...Wet skimming removes particulate matter very well. If you let nutrient matter sit and breakdown in your tank, then yes, it is being mediated 100% biologically. I don't do that, though.
Ok?
Such as? Give me an example.
e.g. The production of most any type of planktonic food, especially below about 10 um. Nitrification-denitrification biofilms.
Biodiversity adds waste. Plain and simple.
Again, not to be rude, but flat wrong. Biodiversity diminishes waste, and that has been proven experimentally.
Nothing gets completely elimiated biologically. It just changes form as we know. With that, it's either recycled or it accumulates in biomass and sediiments. I want it out because I can't provide the ecosystem to deal with it naturally. Some choose to grow populations of organisms and boom/bust. That's uncontrolled - what grows, what dies, etc.
Ok, certainly not trying to tell you how to run your tank, but far and away the easiest to run and what I would consider the most successful tanks are those that had a decent helping of diversity including a lot of meiofauna and infauna. The diversity and quality of the planktonic food produced in these tanks seems to be so much better than what we can provide right now. These tanks just seem to have the fewest problems too. Of course this is very objective, but it just seems like everything works in these tanks. The fish eat and are healthy. The corals grow. The skimmer skims. Everything just runs smoothly. I've not seen this sort of smooth operation without a lot more labor in more sterile tanks, but hey, who knows?
cj
G-money
Premium Member
<a href=showthread.php?s=&postid=7197076#post7197076 target=_blank>Originally posted</a> by MCsaxmaster
If that's your definition of "dirty" then coral reefs in nature are horrendously "dirty." Macroalgae and turf algae grow like crazy as soon as substrate is caged so herbivores can't get in. If macroalgae won't grow in your system when the herbivores are kept away from it then it is a not a very accurate representation of a coral reef.
Tanks don't have the space, diversity, food webs...basically the ecosystem required to support a community of tightly recycled nutrients the way the ocean does. If you're trying to recreate the coral reef, I hope you're dumping several pounds of plankton into it every day, because that's the amount that flows over the same volume of reef as your tank. I know all about herbivore exclusion studies - I even did a paper on the subject. I'm glad to find out that my tank isn't a very accurate representation of a coral reef because macroalgae won't grow.Boy, the corals don't mind, though....I obviously don't have high enough dissolved nutrients or the detritus required to grow macro.....as I sit here wondering in what way I'm "failing"....
Well, I'm not sure how to say this nicely, but you're just plain wrong. Almost all of the mud, sand, and other soft sediment in the world (rivers, lakes, estuaries, mangroves, seagrass beds, etc.) is anoxic within milimeters of the surface.
Yet our tanks are well oxygenated in the upper sand layers? Most sand that I see used in tanks is not much coarser than muddy sediment (Southdown, etc).
Well, I would suggest that the animals are the tools at ones disposal. I'm not sure how one would accomplish many of the tasks done easily in a biodiverse tank, such as feeding heavily with little export of waste, and thus little effort, or feeding of various planktonic organisms. Certainly corals can be kept alive and grown without these things, but I've yet to see what I would consider the same level of success with many organisms without a great deal more husbandry in biodiverse vs. relatively sterile tanks.
All I can say is that it is painfully obvious that you haven't run a tank "the other way". I feed as much as the next guy - for sure. My "sterile" tank blows any other tank I've had away. But I don't expect you to take my word for it. Then again, my main objectives are keeping corals colorful and growing - not building pseudo-"food webs".
e.g. The production of most any type of planktonic food, especially below about 10 um. Nitrification-denitrification biofilms. And why wouldn't anyone have these in their tank? Because "anyone" does.
Again, not to be rude, but flat wrong. Biodiversity diminishes waste, and that has been proven experimentally. Yeah, by all the DSB crashes we've seen in the past few years. :lol: Whatever. As biodiversity increases (or biomass for that matter), more energy is needed to maintain the system. That means you're putting more energy in and since you want to farm everything and tie up this increasing amount of food in organisms, it stays in your tank. It simply amazes me how "natural" reef tank keepers seem to think that nutrients like phosphate are somehow magically eliminated from their system. What amazes me even more is that people think they can operate their tank like it's an ocean. You go ahead and tie up all those nutrients in your system - heck, even export a little algae for good measure. I'll keep them from becoming biomass by skimming heavily and settling the bulk of detritus in my sump where it can be easily dealt with - and removed. Skip the middleman...it's actually easier than growing algae.
...tanks just seem to have the fewest problems too. Of course this is very objective, but it just seems like everything works in these tanks. The fish eat and are healthy. The corals grow. The skimmer skims. Everything just runs smoothly. I've not seen this sort of smooth operation without a lot more labor in more sterile tanks, but hey, who knows?
Wow, you just described my tank! :lol: I'm not here to convince you of anything, much less that "my" way is the only way (because I know that's wrong). But to say that critter farming gives the "best" results is simply not even close to true. You need to see more of those "other" tanks. Most definitely.
If you wouldn't mind, I'd love to see some of your tank pics...I know you know your biology - that's a given. But do you know how to keep a reef tank?? I think that's a fair question, since I've never seen you post a pic or talk about your system(s). I'd at least like to get a visual idea of why you think you have the "better" method(s) - or why I should even put stock in what you say (even though I've tried "your way" and don't like it). Theory and knowledge without practice in reality is worthless. The proof's in the pudding, as they say...
Qwiv
Persistant Perspective
G-Money:
Your original question "Live Rock, is there a point.
Yes, it is to provide a surface area for bacteria. That is the main point. Live rock has shown to be one of the best materials for bacteria to thrive on. The fake stuff works great as well as it will be live. Without it, you have less surface area. You will either need to lower the bio-load, or use another method to remove waste.
The skimmer will not serve this function alone as 80-90% of fish waste comes from the gills in the form of ammonia or a nitrogen compound. The skimmer cannot remove these until bacteria has touched it first. The higher the waste load, the more surface area for bacteria you need. You will then need LR or another replacement.
Sand bed, works much like liverock. Go for it. Lots of aquaculture farms use sand alone. They also replace it and sell there old stuff to us as live sand.
Gravel filters have been shown to not maintain the water quality necessary for most corals we hobbyist keep my more research than I care to even talk about. They do work very well at keeping some coals like elegance, goniopora, and others that come from a high nutrient environment.
Macro and other algeas. Read all the articles about turf filters and there success/failure. They work to a point, but have problems. I am not going to go into that, but the failures out weigh the positives in general. They also require much more room than LR/LS.
Using a synthetic medium. Works, kinda. The hobby started with these. We called them canister filters. They require heavy maintenance as they always need to be cleaned and the medium replaced. If you plan to use them some other way - glue them together = artificial live rock, throw it on the bottom of the tank = similar to a sand bed (good luck with that). I am going to lump zeovit in this section as well as it is fundamentally the same.
Dialysis or water changes. More bio-load = more WC. I just don't have the time to keep up with that, or the money. The problems are obvious. If you have fresh, clean sea water out side your home, go for it. Big public aquariums do.
Secondary reasons for using liverock. Read the many posts by people in the thread. People like liverock for looks, bio diversity, places for the fish to hide, etc. If you don't care for those, then you don't need liverock. Most people I know do.
So, can you keep a tank that will grow coral without liverock (and/or live sand), YES! But it won't have much else in it as your bioload will be limited by the surface area available for bacteria in the tank. Is it enough for what you want to keep, maybe, but you cannot deny that a tank with more surface area for bacteria will support a higher biomass than one with less. If this is the kind of tank you want, I would call it a frag tank or study tank, then go for it. Coral researchers do it all the time and it is very easy. The other 90-99% of reefers out there would not be satisfied with that in there livingroom and that is the point of live rock or some other living substrate until I can teach my fish to use the toilet.
Your original question "Live Rock, is there a point.
Yes, it is to provide a surface area for bacteria. That is the main point. Live rock has shown to be one of the best materials for bacteria to thrive on. The fake stuff works great as well as it will be live. Without it, you have less surface area. You will either need to lower the bio-load, or use another method to remove waste.
The skimmer will not serve this function alone as 80-90% of fish waste comes from the gills in the form of ammonia or a nitrogen compound. The skimmer cannot remove these until bacteria has touched it first. The higher the waste load, the more surface area for bacteria you need. You will then need LR or another replacement.
Sand bed, works much like liverock. Go for it. Lots of aquaculture farms use sand alone. They also replace it and sell there old stuff to us as live sand.
Gravel filters have been shown to not maintain the water quality necessary for most corals we hobbyist keep my more research than I care to even talk about. They do work very well at keeping some coals like elegance, goniopora, and others that come from a high nutrient environment.
Macro and other algeas. Read all the articles about turf filters and there success/failure. They work to a point, but have problems. I am not going to go into that, but the failures out weigh the positives in general. They also require much more room than LR/LS.
Using a synthetic medium. Works, kinda. The hobby started with these. We called them canister filters. They require heavy maintenance as they always need to be cleaned and the medium replaced. If you plan to use them some other way - glue them together = artificial live rock, throw it on the bottom of the tank = similar to a sand bed (good luck with that). I am going to lump zeovit in this section as well as it is fundamentally the same.
Dialysis or water changes. More bio-load = more WC. I just don't have the time to keep up with that, or the money. The problems are obvious. If you have fresh, clean sea water out side your home, go for it. Big public aquariums do.
Secondary reasons for using liverock. Read the many posts by people in the thread. People like liverock for looks, bio diversity, places for the fish to hide, etc. If you don't care for those, then you don't need liverock. Most people I know do.
So, can you keep a tank that will grow coral without liverock (and/or live sand), YES! But it won't have much else in it as your bioload will be limited by the surface area available for bacteria in the tank. Is it enough for what you want to keep, maybe, but you cannot deny that a tank with more surface area for bacteria will support a higher biomass than one with less. If this is the kind of tank you want, I would call it a frag tank or study tank, then go for it. Coral researchers do it all the time and it is very easy. The other 90-99% of reefers out there would not be satisfied with that in there livingroom and that is the point of live rock or some other living substrate until I can teach my fish to use the toilet.
conspicman
New member
ladies and/or gentleman,
We are constantly trying to recreate nature in a little glass box. Is it possible? I doubt it. Maybe we can sterilize and possibly provide a temporary positive environment for our live stock. The one thing that everyone seems to over look when a discussion like this occurs is WATER VOLUME. We always seem to over look the fact that our bio loads are exponentially higher than they are in the oceans. So, Imo no matter what we do we will never be able to compete with the sea's ability to dissipate any large concentrations of waste, nutrients and elements (etc.) Please do not forget about the tremendous amount of surface area that is present. What about the massive UV sterilizer that our seas are exposed to on a daily basis. (for those of you that do not realize that the sun is the most powerful UV on the market. You may want to rethink your negative feeling about UV sterilization.) And of course last but certainly not least the massive skimmer the our oceans has at its disposal (which is every inch of shore line).
In conclusion to my lay opinion: I feal that we are only providing a temporarily hospitable environment that if left alone to work its way through would simply become an extremely over priced coffin for our live stock.
I ask to all. Than why are we so obsessed with this morbid hobby? The answer to that question Imo will always be; we are fascinated by what we cannot completely and/or control.
We are constantly trying to recreate nature in a little glass box. Is it possible? I doubt it. Maybe we can sterilize and possibly provide a temporary positive environment for our live stock. The one thing that everyone seems to over look when a discussion like this occurs is WATER VOLUME. We always seem to over look the fact that our bio loads are exponentially higher than they are in the oceans. So, Imo no matter what we do we will never be able to compete with the sea's ability to dissipate any large concentrations of waste, nutrients and elements (etc.) Please do not forget about the tremendous amount of surface area that is present. What about the massive UV sterilizer that our seas are exposed to on a daily basis. (for those of you that do not realize that the sun is the most powerful UV on the market. You may want to rethink your negative feeling about UV sterilization.) And of course last but certainly not least the massive skimmer the our oceans has at its disposal (which is every inch of shore line).
In conclusion to my lay opinion: I feal that we are only providing a temporarily hospitable environment that if left alone to work its way through would simply become an extremely over priced coffin for our live stock.
I ask to all. Than why are we so obsessed with this morbid hobby? The answer to that question Imo will always be; we are fascinated by what we cannot completely and/or control.
MCsaxmaster
New member
Tanks don't have the space, diversity, food webs...basically the ecosystem required to support a community of tightly recycled nutrients the way the ocean does. If you're trying to recreate the coral reef, I hope you're dumping several pounds of plankton into it every day, because that's the amount that flows over the same volume of reef as your tank. I know all about herbivore exclusion studies - I even did a paper on the subject. I'm glad to find out that my tank isn't a very accurate representation of a coral reef because macroalgae won't grow. Boy, the corals don't mind, though....I obviously don't have high enough dissolved nutrients or the detritus required to grow macro.....as I sit here wondering in what way I'm "failing"....
I'm afraid maybe we're misunderstanding each other a bit. Reeftanks, by their nature, are artificial structures. I think a goal for most reefkeepers is to recreate the conditions and appearance of a reef as much as feasible within cost and labor constraints. As such, there are always aspects that manifest that aren't realistic of the natural reef. If benthic algae isn't constrained by herbivores then a tank isn't modeling the real system. This isn't necessarily a bad thing, and I didn't mean to imply it is a failure per se, but the tank is not replicating a coral reef in some very fundamental ways.
Also, nutrients are recyced over a very broad area in nature encompassing many distinct ecosystems. Thus, coral reefs (at least a typical forereef and/or reef flat) doesn't totally recycle its nutrients. In fact, they barely do. The nutrients are recycled through tight coupling of the reef/lagoon/seagrass/mangrove/near oceanic system where some pelagic, but mostly benthic processes are paramount.
Yet our tanks are well oxygenated in the upper sand layers? Most sand that I see used in tanks is not much coarser than muddy sediment (Southdown, etc).
It's a bit odd to be totally honest, and not expected. There isn't nearly enough data on reef tanks to be certain that all or perhaps even most of them are oxic thoughout, but the sandbed "study" that folks did with Dr. Shimek seems to suggest it. As for why that is, my guess would be that there is relatively less being decomposed in our sandbeds than in a similar section of sediment in nature.
There are organsims that are transient though the anoxic sediments, but I'm not aware of many animals that respire without oxygen present. Perhaps you can help me out with that? Bacteria - sure. But I must plead ignorance to the multitude of non-bacterial species that you claim live in anoxic conditions.
Any sort of infaunal or meiofaunal organism. Mostly these are various worm phyla, crustaceans, forams, ciliates, molluscs etc. Usually they pump water from above (oxic) so they can breath or utilize anaerobic metabolic pathways. The Invert. Zoology textbook by Brusca and Brusca is the classicly used text for invertebrate phyla, if you're able to track it down. You should also be able to find more info. on marine in/meiofauna in a marine biology text, e.g. Nybakin's.
Lots of the bacteria there are something I don't want thriving in my tank, either. Maybe if my tank was an estuarian habitat or mangrove mud flat, but my tank, despite your reluctance, is indeed quite hospitible to the corals - and that's why the tank exists.
Sure, couldn't agree more. Too many bacteria is bad. Usually the conditions that foster that are a large abundance of labile detritus (doesn't happen unless someone is seriously, seriously overfeeding) or very low water flow for some bacteria (now good for the tank anyway). If the tank has low waterflow and you're throwing in a handful of mangrove leaves everyday, you'll probably get something more like a mangrove than a reef. Although I will also point out that some corals are really common in mangroves
I also never meant to suggest your tank was inhospitable for certain zooxanthellate corals. I don't think live rock is necessary to keep many of them alive and grow them, but I think in the context of a reef tank, with fish, corals, and various other invertebrates, it would be much more difficult to do so without the biotic mediation live rock provides.
All I can say is that it is painfully obvious that you haven't run a tank "the other way". I feed as much as the next guy - for sure. My "sterile" tank blows any other tank I've had away. But I don't expect you to take my word for it. Then again, my main objectives are keeping corals colorful and growing - not building pseudo-"food webs".
I do have the privelage of knowing a few people that have been in the hobby 10+ years and have run tanks many, many ways. I've also had the opportunity to see tanks run many ways. From what I've seen and through talking with people that have tried it all it seems to me that tanks with a moderate amount of live rock, a sand bed, have a solid infaunal/meiofaunal population, get fed well, and usually (but not always) have a strong method of nutrient export are the most successful and the easiest to keep. They also seem to be closer to nature, at least they look more like the reefs I've been to than systems that deviate significantly from these conditions.
e.g. The production of most any type of planktonic food, especially below about 10 um. Nitrification-denitrification biofilms. And why wouldn't anyone have these in their tank? Because "anyone" does.
I don't follow.
Yeah, by all the DSB crashes we've seen in the past few years. Whatever
Well, a couple of things: 1. what is a "deep sand bed crash" really? 2. if there is something wrong with deep sand beds, something inherent, why don't they all crash? Why are there so, so many really great tanks with sand beds? e.g., Joe Burger's tank. 3. you've never seen a person with a shallow sand bed, or no sand, kill things? Tanks "crash" and animals die because we as aquarists make mistakes, or because of good 'ol Murphy's law. Fish, corals, and many other animals can be kept in tanks with all sorts of bottom coverings. What does that have to do with live rock though?
That means you're putting more energy in and since you want to farm everything and tie up this increasing amount of food in organisms, it stays in your tank. It simply amazes me how "natural" reef tank keepers seem to think that nutrients like phosphate are somehow magically eliminated from their system.
Sure, we put food into tanks specifically for the purpose of keeping some of it there in the form of growth in our animals. Of course one has to remove these nutrients at some point...unless there is an antimatter generator installed Carbon in food added to the system is lost as CO2 (mostly) or deposited as CaCO3 (mostly). Nitrogen is put into tissues or sunk in CaCO3 matrices. Some is undoubtedly gassed off as NH3, N2, N2O, etc. Whatever is left is removed in skimmate, harvested algae, water changes, activated carbon, etc. Phosphorus is put into tissue, sequestered in CaCO3 (mostly) or removed with skimmate, algae, activated carbon, etc.
In a tank with a fish and nitrifying and heterotrophic bacteria, all the N and P in the food will end up dissolved in the water. With the same fish and food but some rock and sand with detritivores, corals, coralline algae, etc. a lot of the N and P in the food ends up as growth in these organisms or sequestered geologically. In the first case a lot of N and P needs to get removed. In the second less needs to be removed.
What amazes me even more is that people think they can operate their tank like it's an ocean. You go ahead and tie up all those nutrients in your system - heck, even export a little algae for good measure. I'll keep them from becoming biomass by skimming heavily and settling the bulk of detritus in my sump where it can be easily dealt with - and removed. Skip the middleman...it's actually easier than growing algae.
Ok, go ahead. No reason you shouldn't run your tank this way. Of course, with the same degree of maintenance, some good rock, a sand bed, and maybe a refugium a lot of folks get similar good results with their fish and corals, but also have the pleasure of growing things like sponges, ascidians, feather duster worms, etc. I've yet to see that properly maintained barebottom tanks are in any way less maintenance or more likely to grow healthy fish and corals than tanks with sand, rock, and a refugium. They both seem to do these. The latter, however, seems to also provide a hospitable environment for other reef animals while the former seems less able to do this IME.
For the record, I think you mean subjective. If it were objective, we wouldn't be having this "debate". To be objective is to be free of bias...
That's probably why I shouldn't type when it's late and I'm exhausted
Best,
Chris
I'm afraid maybe we're misunderstanding each other a bit. Reeftanks, by their nature, are artificial structures. I think a goal for most reefkeepers is to recreate the conditions and appearance of a reef as much as feasible within cost and labor constraints. As such, there are always aspects that manifest that aren't realistic of the natural reef. If benthic algae isn't constrained by herbivores then a tank isn't modeling the real system. This isn't necessarily a bad thing, and I didn't mean to imply it is a failure per se, but the tank is not replicating a coral reef in some very fundamental ways.
Also, nutrients are recyced over a very broad area in nature encompassing many distinct ecosystems. Thus, coral reefs (at least a typical forereef and/or reef flat) doesn't totally recycle its nutrients. In fact, they barely do. The nutrients are recycled through tight coupling of the reef/lagoon/seagrass/mangrove/near oceanic system where some pelagic, but mostly benthic processes are paramount.
Yet our tanks are well oxygenated in the upper sand layers? Most sand that I see used in tanks is not much coarser than muddy sediment (Southdown, etc).
It's a bit odd to be totally honest, and not expected. There isn't nearly enough data on reef tanks to be certain that all or perhaps even most of them are oxic thoughout, but the sandbed "study" that folks did with Dr. Shimek seems to suggest it. As for why that is, my guess would be that there is relatively less being decomposed in our sandbeds than in a similar section of sediment in nature.
There are organsims that are transient though the anoxic sediments, but I'm not aware of many animals that respire without oxygen present. Perhaps you can help me out with that? Bacteria - sure. But I must plead ignorance to the multitude of non-bacterial species that you claim live in anoxic conditions.
Any sort of infaunal or meiofaunal organism. Mostly these are various worm phyla, crustaceans, forams, ciliates, molluscs etc. Usually they pump water from above (oxic) so they can breath or utilize anaerobic metabolic pathways. The Invert. Zoology textbook by Brusca and Brusca is the classicly used text for invertebrate phyla, if you're able to track it down. You should also be able to find more info. on marine in/meiofauna in a marine biology text, e.g. Nybakin's.
Lots of the bacteria there are something I don't want thriving in my tank, either. Maybe if my tank was an estuarian habitat or mangrove mud flat, but my tank, despite your reluctance, is indeed quite hospitible to the corals - and that's why the tank exists.
Sure, couldn't agree more. Too many bacteria is bad. Usually the conditions that foster that are a large abundance of labile detritus (doesn't happen unless someone is seriously, seriously overfeeding) or very low water flow for some bacteria (now good for the tank anyway). If the tank has low waterflow and you're throwing in a handful of mangrove leaves everyday, you'll probably get something more like a mangrove than a reef. Although I will also point out that some corals are really common in mangroves
I also never meant to suggest your tank was inhospitable for certain zooxanthellate corals. I don't think live rock is necessary to keep many of them alive and grow them, but I think in the context of a reef tank, with fish, corals, and various other invertebrates, it would be much more difficult to do so without the biotic mediation live rock provides.
All I can say is that it is painfully obvious that you haven't run a tank "the other way". I feed as much as the next guy - for sure. My "sterile" tank blows any other tank I've had away. But I don't expect you to take my word for it. Then again, my main objectives are keeping corals colorful and growing - not building pseudo-"food webs".
I do have the privelage of knowing a few people that have been in the hobby 10+ years and have run tanks many, many ways. I've also had the opportunity to see tanks run many ways. From what I've seen and through talking with people that have tried it all it seems to me that tanks with a moderate amount of live rock, a sand bed, have a solid infaunal/meiofaunal population, get fed well, and usually (but not always) have a strong method of nutrient export are the most successful and the easiest to keep. They also seem to be closer to nature, at least they look more like the reefs I've been to than systems that deviate significantly from these conditions.
e.g. The production of most any type of planktonic food, especially below about 10 um. Nitrification-denitrification biofilms. And why wouldn't anyone have these in their tank? Because "anyone" does.
I don't follow.
Yeah, by all the DSB crashes we've seen in the past few years. Whatever
Well, a couple of things: 1. what is a "deep sand bed crash" really? 2. if there is something wrong with deep sand beds, something inherent, why don't they all crash? Why are there so, so many really great tanks with sand beds? e.g., Joe Burger's tank. 3. you've never seen a person with a shallow sand bed, or no sand, kill things? Tanks "crash" and animals die because we as aquarists make mistakes, or because of good 'ol Murphy's law. Fish, corals, and many other animals can be kept in tanks with all sorts of bottom coverings. What does that have to do with live rock though?
That means you're putting more energy in and since you want to farm everything and tie up this increasing amount of food in organisms, it stays in your tank. It simply amazes me how "natural" reef tank keepers seem to think that nutrients like phosphate are somehow magically eliminated from their system.
Sure, we put food into tanks specifically for the purpose of keeping some of it there in the form of growth in our animals. Of course one has to remove these nutrients at some point...unless there is an antimatter generator installed
Carbon in food added to the system is lost as CO2 (mostly) or deposited as CaCO3 (mostly). Nitrogen is put into tissues or sunk in CaCO3 matrices. Some is undoubtedly gassed off as NH3, N2, N2O, etc. Whatever is left is removed in skimmate, harvested algae, water changes, activated carbon, etc. Phosphorus is put into tissue, sequestered in CaCO3 (mostly) or removed with skimmate, algae, activated carbon, etc.In a tank with a fish and nitrifying and heterotrophic bacteria, all the N and P in the food will end up dissolved in the water. With the same fish and food but some rock and sand with detritivores, corals, coralline algae, etc. a lot of the N and P in the food ends up as growth in these organisms or sequestered geologically. In the first case a lot of N and P needs to get removed. In the second less needs to be removed.
What amazes me even more is that people think they can operate their tank like it's an ocean. You go ahead and tie up all those nutrients in your system - heck, even export a little algae for good measure. I'll keep them from becoming biomass by skimming heavily and settling the bulk of detritus in my sump where it can be easily dealt with - and removed. Skip the middleman...it's actually easier than growing algae.
Ok, go ahead. No reason you shouldn't run your tank this way. Of course, with the same degree of maintenance, some good rock, a sand bed, and maybe a refugium a lot of folks get similar good results with their fish and corals, but also have the pleasure of growing things like sponges, ascidians, feather duster worms, etc. I've yet to see that properly maintained barebottom tanks are in any way less maintenance or more likely to grow healthy fish and corals than tanks with sand, rock, and a refugium. They both seem to do these. The latter, however, seems to also provide a hospitable environment for other reef animals while the former seems less able to do this IME.
For the record, I think you mean subjective. If it were objective, we wouldn't be having this "debate". To be objective is to be free of bias...
That's probably why I shouldn't type when it's late and I'm exhausted
Best,
Chris
MCsaxmaster
New member
The one thing that everyone seems to over look when a discussion like this occurs is WATER VOLUME. We always seem to over look the fact that our bio loads are exponentially higher than they are in the oceans. So, Imo no matter what we do we will never be able to compete with the sea's ability to dissipate any large concentrations of waste, nutrients and elements (etc.)
Yes and no. I think you're very right to point this out, and I think it definitely has an effect on the dissipation of certain compounds and thus their affects, as well as the predation pressure on plankters. However, most of the processes important for nutrient cycling on reefs happen on and in the benthos, not in the water column. In some cases aquariums may not be too far off in the amount of fish they have to a given amount of substrate. Still higher usually, but not too much higher (hence our ability to provide enough food yet reeflike nutrient concentrations).
In conclusion to my lay opinion: I feal that we are only providing a temporarily hospitable environment that if left alone to work its way through would simply become an extremely over priced coffin for our live stock.
Couldn't agree more. Animal husbandry, especially reefkeeping, is very much like driving a car: constant, small adjustments are required for things to run smoothly. Without our constant intervention a tank just doesn't work. IME the most successful aquarists are the ones that know how to 'read' their tanks and make the slightest of alterrations when necessary.
Chris
Yes and no. I think you're very right to point this out, and I think it definitely has an effect on the dissipation of certain compounds and thus their affects, as well as the predation pressure on plankters. However, most of the processes important for nutrient cycling on reefs happen on and in the benthos, not in the water column. In some cases aquariums may not be too far off in the amount of fish they have to a given amount of substrate. Still higher usually, but not too much higher (hence our ability to provide enough food yet reeflike nutrient concentrations).
In conclusion to my lay opinion: I feal that we are only providing a temporarily hospitable environment that if left alone to work its way through would simply become an extremely over priced coffin for our live stock.
Couldn't agree more. Animal husbandry, especially reefkeeping, is very much like driving a car: constant, small adjustments are required for things to run smoothly. Without our constant intervention a tank just doesn't work. IME the most successful aquarists are the ones that know how to 'read' their tanks and make the slightest of alterrations when necessary.
Chris
G-money
Premium Member
Thanks Chris.
I think I'm satisfied with our conversation.
At least, it's at a point where I don't feel the need to rebut.
We're in agreement that live rock has its place in the reef tank. Although we use it for the same basic property (surface area), you want yours teeming with as much diversity as possible. I don't. I think I'll leave it at that unless you'd like me to clarify anything I've said.
I think I'm satisfied with our conversation.
At least, it's at a point where I don't feel the need to rebut.
We're in agreement that live rock has its place in the reef tank. Although we use it for the same basic property (surface area), you want yours teeming with as much diversity as possible. I don't. I think I'll leave it at that unless you'd like me to clarify anything I've said.
MCsaxmaster
New member
Nah, I think I'm satisfied with things at this point
Chris
Chris
