Live Rock...Is there a point??

[sttroyiii]

I let the ammonia and such spike really high when I set up my first tank and let it cycle. All of the coralline bleached out, and Im sure most everything was dead. I essentially cooked it. Slowly the coralline started coming back. It wasnt until I started adding more pieces of live rock that I got visible 'life'. Now I too, am guilty of staring at the rock for long periods of time I wont disclose, hehe. I think the benefits of live rock are far more numerous than the cons. If you didnt have live rock, where would all of the bugs hide? They would get eaten a lot easier. What would you anchor your corals too? I think the best benefit are hitch hikers. Of course people talk about their problems more than good things that happen to them. So there are bad hitch hikers, but what about all of the good ones. It seems to me the only way to cheaply add all of the tiny brittle stars, pods, etc. is through live rock. You get something to mount stuff too, plus lots of life. Granted Ive never picked up anything too bad yet. I like all of the surprises you get with live rock. It gives you something to talk about, whether bad or good. Successes and failures make people want to talk and thats why we are here. We talk and we learn. I dont think you have to have LR, but arent all of the reefs built up live rock? I dont think corals and stuff just spring up out of the sand bottom. I think of LR being the equivalent to deep sand beds as far as denitrifying goes.

I just bought 40lbs. of live rock yesterday, to start a 37 gallon tank. I made sure to get uncured, as I would like a little of everything. I have been disappointed with the life I got when I ordered cured rock on my current tank. Im going to make sure to keep the spikes in check to preserve as much life as I can. Anything that live is just stuff I dont have to buy.

 

[jobiwan]

I set up my 60 entirely with cultured florida live rock (Dale Barger of Gulfview Marine, GARF mentions him also), it is very dense, heavy rock, low porosity I'm fairly sure, but it is absolutely loaded with diverse life, Dale is licensed to dump "base rock" on some patch of sand out in the gulf, he collects it several years later, it is just about the only way to legally get live caribbean corals, he ships so well that most corals came in alive and are thriving in my tank, along with gorgonians, sponges, complex algaes and of course lots of coralline, it cycled in no time, it was like getting an instant established tank. If you started with just base rock you wouldn't have the biodiversity initially, and I think it would take a long time to get it going, you could do it with lots of time and patience I suppose, I don't think porosity is that important, but it couldn't hurt to have it either, a mixture of cultured rock and cured live rock is my personal preference...My first SW had an air driven undergravel with dolomite substrate and lots of dead coral skeletons, IMHO live rock is the only way to go, I know there are other ways to succede, but they aren't for me....

 

[sttroyiii]

I get most of my stuff from a LFS called Cappuccino Bay not too far from Atlanta. http://www.cappuccinobayaquarium.com/

All of their coral tanks have tons of live rock in them. They will completely fill a tank halfway with LR and then put a rack on top with the corals. They have bins and bins of the stuff with their water pumping through it all. They wont let you buy any of this rock! Its so pretty and covered with life too. The rock for sale is in the back by itself and isnt too much to brag about. Im pretty sure if you asked why you cant buy the other stuff, it would because of biological filtration.

They have racks and racks with sps frags both farmed and otherwise. Lots and lots of clams. Their specialty is corals though. The quality is the best Ive seen around Atlanta.

 

[NoSchwag]

<a href=showthread.php?s=&postid=7054611#post7054611 target=_blank>Originally posted</a> by brentp
I used to always wonder how people with grow out tanks with no live rock managed to keep corals growing and thriving.

Until I ran my 150 gallon tank for about 6 months with corals (mostly SPS) and clams sitting on eggcrate. I also left the fish in the tank. I was paranoid that nitrates would go through the roof so I tested at least weakly with a Salifert kit. No measurable nitrates ever.

If I could figure out something that looked good to put my corals on that would not be the detritus trap that live rock is, I'd happily get rid of the live rock.

You said it.. Why do I need all the nitrifying properties of rock when my skimmer takes care of EVERYTHING? Live rock, to me, serves no purpose other than a pretty place to put corals.

 

[MCsaxmaster]

You realize that a protein skimmer cannot remove inorganic nurtrients like ammonia, nitrate, and phosphate whatesoever do you not? How can it 'take care of everything?'

 

[brentp]

<a href=showthread.php?s=&postid=7071951#post7071951 target=_blank>Originally posted</a> by MCsaxmaster
You realize that a protein skimmer cannot remove inorganic nurtrients like ammonia, nitrate, and phosphate whatesoever do you not? How can it 'take care of everything?'

By getting it out before it breaks down. I ran my tank tank like that for 6 months with 0 nitrates. I'm pretty sure it wasn't magic.

I'm not saying that live rock isn't great. You just don't have to have it for denitrification unless you plan on leaving a bunch of crap to rot in your tank. People with long term success don't do that whether they have a ton of live rock, a little live rock, BB, DSB.

Will the stuff in my frag tank die if I don't put live rock in there?:lol:

 

[NoSchwag]

You realize that a protein skimmer cannot remove inorganic nurtrients like ammonia, nitrate, and phosphate whatesoever do you not? How can it 'take care of everything?'

I run a UV also.. That, my skimmer, and my flow takes care of EVERYTHING.

I am under the impression that one could pack a tank with 234293486 fish, have no sand and no rock, feed 10 x's a day, and still have very low nutrients.

 

[MCsaxmaster]

But, you guys realize that fish excrete significant amounts of ammonia and phosphate. Skimmers, UV sterilizers, etc. can't do a thing with these inorganic nutrients. Sure a skimmer can remove organics such as what's in solid fish waste, but the majority of the waste they produce is in these inorganic forms. Without sufficient assimilation of these nutrients or nitrification for the ammonia, they just build up.

Without sufficient biological uptake and/or nitrification going on in some sort of substrate, the tank will be perpetually "cycling." Rather, it will never "cycle" because there's not substrate to mediate uptake and nitrification.

Best,

Chris

 

[brentp]

<a href=showthread.php?s=&postid=7072859#post7072859 target=_blank>Originally posted</a> by MCsaxmaster
But, you guys realize that fish excrete significant amounts of ammonia and phosphate. Skimmers, UV sterilizers, etc. can't do a thing with these inorganic nutrients. Sure a skimmer can remove organics such as what's in solid fish waste, but the majority of the waste they produce is in these inorganic forms. Without sufficient assimilation of these nutrients or nitrification for the ammonia, they just build up.

Without sufficient biological uptake and/or nitrification going on in some sort of substrate, the tank will be perpetually "cycling." Rather, it will never "cycle" because there's not substrate to mediate uptake and nitrification.

Best,

Chris

Bacteria can be skimmed out though. And live rock or no live rock your relying on them to do what they do best. Eat and reproduce. Obviously if you import more nutrients than you are exporting you are going to run into problems in any system.

 

[MiddletonMark]

<a href=showthread.php?s=&postid=6927570#post6927570 target=_blank>Originally posted</a> by BeanAnimal
I have as much biodiversity as the guys who spent a fortune on fiji or tonga rock. I don't have the hitchhikers though. Every frag you trade will add diversity to your tank and to that of the person you trade with. It is also a reason that so many "bad" things are propogating through the hobby.

I'm confused ... you don't have hitchhikers, but you have diversity? Aren't they one in the same?

Personally, I have not gotten the number + variety of sponges, worms, featherdusters, pods, etc etc from the plugs/tiny LR pieces from frags that I got on live rock. I've gotten a few - but to be honest I have more sponges/tunicates growing off my Crocea than I have growing from all the frag plugs in my system [which is 90% aquacultured coral].

You can have it one way [no hitchhikers/pests] or the other [as much diversity] ... but IME, you can't have it both ways [all the diversity, no pests].

Given I've had zero problematic LR pests [maybe 75-100# of rock purchased] and three coral-pests from the 50 or so frags I've bought ... seems to me, that frags are more pest-ridden than LR. Supposed it depends on the LR, but that's my experience.

 

[G-money]

<a href=showthread.php?s=&postid=7072859#post7072859 target=_blank>Originally posted</a> by MCsaxmaster
But, you guys realize that fish excrete significant amounts of ammonia and phosphate. Skimmers, UV sterilizers, etc. can't do a thing with these inorganic nutrients. Sure a skimmer can remove organics such as what's in solid fish waste, but the majority of the waste they produce is in these inorganic forms. Without sufficient assimilation of these nutrients or nitrification for the ammonia, they just build up.

Without sufficient biological uptake and/or nitrification going on in some sort of substrate, the tank will be perpetually "cycling." Rather, it will never "cycle" because there's not substrate to mediate uptake and nitrification.

Best,

Chris

Assimilation, as you said. Algae can utilize both PO4 and ammonia right out of the water. Not necessarily "nuisance" algae, either. In fact, planktonic forms use it most efficiently. Very skimmable. Zoox also use it.

We're also not taking into account the large variable of biomass density. In a tank with very few fish and lots of coral, the need for live rock would be minimal IMO.

We also neglect that bacteria will still grow on every available surface in the system - the glass, plumbing and everything else. Not nearly as much surface area as rock, but functional nonetheless. With a low non-coral biomass, it would still be most functional without a doubt. People are doing it as we speak in their frag tanks and whatnot...

Nitrate levels have to go pretty high to negatively impact most corals. Water changes would mitigate this as well...

 

[MCsaxmaster]

Ok. Some comments up the thread a bit that one could have an very large fish population and feed them heavily while needing nothing more than a skimmer is really what I was contending. That's just not functionally possible.

As for being able to grow corals without live rock, I have no doubt this is possible. I have to ask though, why would anyone want to do that? It seems a bit like growing plants hydroponically and calling it a forest to me. Plus, a system like that is going to lack many natural feedbacks and be much more prone to crashing/problems. Hydroponics work because of pretty serious monitoring. Without that they wouldn't. I'm not sure that's possible in reef tanks.

cj

 

[G-money]

I hear you Chris. But IME, hydroponics is mixing up the proper solutions and away you go. If there weren't benefits to be had over soil, it wouldn't be done.

There are also people that believe that an incomplete ecosystem is more prone to crash the more variables that are put into it - so long as it stays incomplete (like every reef tank on Earth). We ask ourselves what corals need. It ain't much. I don't really strive for all that biodiversity because I end up with more than I want anyway. More mouths to feed always equals more potential for problems. Always.

I would ask myself why I would want to make a frag tank look like a display tank.

 

[HowardW]

To me, live rock is to reefs what trees are to tropical rain forests, and I feel that live rock teeming with critters is very beneficial to a successful reef tank over the long term even if it cannot be scientifically explained.

The live substrate, the corals, the inverts, the fish, the live rock, all the tiny critters......it's all an important part of an extremely complex ecosystem and each has its purpose.

How's that??

 

[G-money]

For the record, I'm not doubting live rock's usefullness at all.
If we want to talk about necessity, no, it's absolutely not necessary. Not in all cases. Do I use it? Yup.

 

[MCsaxmaster]

<a href=showthread.php?s=&postid=7076134#post7076134 target=_blank>Originally posted</a> by G-money
I hear you Chris. But IME, hydroponics is mixing up the proper solutions and away you go. If there weren't benefits to be had over soil, it wouldn't be done.

There are also people that believe that an incomplete ecosystem is more prone to crash the more variables that are put into it - so long as it stays incomplete (like every reef tank on Earth). We ask ourselves what corals need. It ain't much. I don't really strive for all that biodiversity because I end up with more than I want anyway. More mouths to feed always equals more potential for problems. Always.

I would ask myself why I would want to make a frag tank look like a display tank.

I'm not sure I'm quite following to tell you the truth. Complex food webs are far more stable than simple ones though.

cj

 

[G-money]

Food webs assume completeness. Are you assuming that any given reef tank will have a complete food web? While I can't prove it either way, my money is on every reef tank being an incomplete food web. For instance, the basis of most natural ocean food webs - phytoplankton and plankton in general are not largely present in our systems. How can you call that a food web? If it were a food web, you wouldn't have to put anything into it. (that is, feed)

I know you and I generally see things differently, but I don't know how to explain it any other way. More biomass means you are supporting more respiration in your tank. Let's say the power goes out, or an area of your sand becomes anoxic, there is a mass die-off of any given "niche-filler" or a food item is lacking for a certain niche-filler....you get the idea. Any way you look at it, more biomass is more potential nutrients and less under your control.

If I can achieve the same thing non-biologically, it is far more stable because it is completely under my control, not the fate of the organisms I am relying on. Sure, there are some things (like nitrification) that are most easily and effectively done biologically - and with little associated risk. I'd never doubt that. But to say my tank is more stable because I have this or that population of worm or tunicate or whatever....and I rely on it is just not within my logic.

Now in nature, I'd never argue this point.
In a reef tank...an incomplete ecosystem, it's a different story. I like to look at little critters as much as anyone. But I don''t rely on them and I certainly don't expect them to take care of my tank.

 

[sparkey_burke]

in my opinionI like fige and and the flat gulf rock

 

[mr.wilson]

A "live rock free" reef tank doesn't exist, as live corals are, in effect, live rock. Biological process is carried out on its calcareous core and surface. Wherever detritus forms, nitrifying bacteria will flourish.

If you were to argue that a reef tank can be maintained without nitrification, you would have to sterilize all surfaces and have fish and water only. Of course this model could no longer be deemed as a "reef tank". Once you introduce a substrate (including egg-crate) you have nitrification.

I agree that live rock is a bio-load, but it is easily balanced in a modern aquarium. it fosters pro-biotics that will out-compete with nuisance algae, it harbours live zooplankton, and it is a vital part of the buffering system.

Live rock can be minimized, but not completely dismissed.

 

[MCsaxmaster]

Food webs assume completeness. Are you assuming that any given reef tank will have a complete food web? While I can't prove it either way, my money is on every reef tank being an incomplete food web. For instance, the basis of most natural ocean food webs - phytoplankton and plankton in general are not largely present in our systems. How can you call that a food web?

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).

If it were a food web, you wouldn't have to put anything into it. (that is, feed)

You don't want anything in the tank to grow?

I know you and I generally see things differently, but I don't know how to explain it any other way. More biomass means you are supporting more respiration in your tank.

Sure. So have live rock and a sand bed and one fewer fish; problem solved. BOD also has a lot to do with the amount of decompostion going on. Our reef tanks don't have tons of decomposition happening at any one time. Now, set up a tank to mimic mangroves and dump in a bunch of leaves and bird droppings everyday and you'll see a pretty serious drop at night. But as Eric's articles recently in RK have shown, it doesn't particularly matter what is in the tank. There is always a decent BOD. Reverse lighted refugiums are probably a good idea no matter what is in the tank.

Let's say the power goes out, or an area of your sand becomes anoxic, there is a mass die-off of any given "niche-filler" or a food item is lacking for a certain niche-filler....you get the idea.

Well, power outages are bad for tanks. In a tank with fish but no rock or sand you're not going to have that much longer than a tank with all three. 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.

Any way you look at it, more biomass is more potential nutrients and less under your control.

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.

If I can achieve the same thing non-biologically, it is far more stable because it is completely under my control, not the fate of the organisms I am relying on.

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.

Sure, there are some things (like nitrification) that are most easily and effectively done biologically - and with little associated risk. I'd never doubt that. But to say my tank is more stable because I have this or that population of worm or tunicate or whatever....and I rely on it is just not within my logic.

Ok. Nothing says this must be done, but it is an aweful lot easier to let organisms do the work naturally than to try to deal with every little transformation that needs to happen. Our technology just simply can't provide most of the functions that reefs and adjacent habitats provide.

Now in nature, I'd never argue this point. In a reef tank...an incomplete ecosystem, it's a different story. I like to look at little critters as much as anyone. But I don''t rely on them and I certainly don't expect them to take care of my tank.

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.

As for not relying on creatures to perform certain transformations in your tank, that's fine with me. The easiest-to-run, most succesful tanks I've ever seen tend to do this, and these were also the most naturalistic in appearance and behavior (and the most visually appealing to my eyes) as compared to a reef. I don't see that avoiding live rock makes keeping a tank any easier or that any of the animals in it are likely to perform better. If anything it seems just the opposite so personally I don't see any reason to try it. It probably can be done, but I've also seen great tanks with deep beds of crushed coral, or Acropora doing very well under NO fluorescent bulbs. Sure, these things can be done, but they don't seem like the easiest route, so I really don't see the point in entertaining them to be honest.

Best,

Chris