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Live Rock Dilemma

Back by popular demand!

Since we removed this infamous 1995 article, we’ve had constant requests to bring it back. Answering letters like these daily and trying to tell the facts in today’s market makes this information more useful than ever. I hope it answers your questions.

Enjoy!

Angela Chanelli

Q
From: Max Traber, California

From the sound of these questions you’d think we weren’t already saturated with information on this subject. Surprisingly, these are some of the most asked questions we receive. Perhaps not a new topic to some, but everyone has to get the scoop sooner or later.

In this article I will explain some of the misconceptions and propaganda surrounding live rock, and hopefully do so without putting anyone to sleep. I know a lot of you are probably thinking this is a ridiculously simple topic to cover in such detail, as well as redundant, but our mail inquiries on the subject indicates it still needs addressing.

In answering thousands of inquires monthly, the “cured/pre-cured/uncured/transshipped rock” situation is one I answer literally every day. The same few questions are stated in different ways, and therefore in this article I will do the same and hopefully cover all the angles. And yes, it seems a bit redundant to me too at times. Apologies in advance. If you’re here just to buy some rock, you can do that here

Pre-Cured, Cured, Fresh… What’s the deal???

Since this article was originally written (in 1995), one thing has become painfully obvious: The term “cured” has become little more than a meaningless buzzword used to sell live rock. Very little rock today is actually cured, although a lot is sold as such. This practice is so common that it has received mention in at least two recently published books! Keep this in mind when shopping for live rock.

Does anyone still cure rock?

Yes, but it’s exceedingly rare today. You can possibly still get cured rock from a few shops who still do it, and get money for doing so, but not at a transshipped price. That’s the point that spurred this article years ago. Our praise to our fellow trades people who still cure rock and get good money for doing it. Whether or not you need cured rock is a matter of patience, and whether you’re starting a new tank or have an already inhabited tank. All live rock will “cure” in your tank or someone else’s, given typically 2-4 weeks.

Pre-Cured or “Cured In Fiji” Rock

So what is the difference in “pre-cured, “cured” and “fresh” live rock? Probably the most direct answer is simply marketing, but before we explain the differences, or lack thereof, the first thing you may want to consider is the age old adage, “people will tell you anything to sell something”, and with live rock, this seems to get worse all the time. There are all sorts of misleading terms that are applied to live rock, when in reality, any rock imported from anywhere in the Pacific will require thorough curing once it’s made the trip from the origin to the US, regardless what has supposedly been done with it at the origin because it’s the trip from the origin to the US that has it in need of “curing”.

Do me a favor here- think about the term “Pre-Cured”, then look again at the last sentence of the previous paragraph. Are we beginning to see that none of these terms make any sense? The term ‘pre-cured’ is a buzzword used for selling live rock in an over saturated market.” A more accurate term would be “pre-cleaned”, as in, cleaned before export, the rock is rinsed of sediment, algae, sponges, etc. that obviously won’t survive have been removed. This is typically what exporters have long considered “cured” or “pre-cured”, although advertising and consumer assumptions may differ. With that said, it’s important to realize that an exporters definition of “cured” and a hobbyists definition of “cured” are often two completely different things.

Fresh Rock

This is also known as “uncured”, which is what rock, supposedly “cured” at the origin overseas will be by the time it gets to the US, and what virtually all mail order rock is, despite how it may be advertised. When you hear the term “fresh rock”, forget the definition of the word “fresh” as you know it. When referring to live rock, fresh simply means it’s “new”, as in it was just imported. “Fresh”, as in clean and pollution free has nothing to do with it. And is case it isn’t obvious, “fresh” rock is not safe for an aquarium containing animals. If the dealer you obtain the rock from has not unboxed and kept the rock in water for at lest several weeks, rock originating from overseas is not safe for inhabited tanks.

So what’s the problem with newly imported rock? Well, nothing, if it were speed shipped submerged in water with plenty of oxygen, but it’s not. It’s imported dry, and it’s out of water for days. Are you getting the picture yet? Look at these facts… The most popular rock used in reef tanks today is imported from the South Pacific, mainly Fiji, which is essentially several zillion light years from us as far as the life on and in the rock is concerned. Dealers offering “transship” prices (such as ours) rarely place rock in water the before sale- it remains boxed until sale, which means virtually all mail order rock will have likely been dry from the time it was boxed in Fiji until you place it in your tank. Are the terms “pre-cured”, “cured in Fiji” and “fresh” beginning to sound more like marketing?

From the time the rock is boxed in Fiji until it reaches a anyone in the states, it will have already been out of water for several days. By the time it gets back in water, which will most likely be in your tank, 2-5 days may have passed. What kind of condition do you think rock will be in at this time? Will it be “cured”? The importation process inevitably results in losses of varying degree regardless what has been done with it while in Fiji. At this point you may be thinking, what good is “pre-cured” or “cured, when it’s done before export? That’s right- nothing.

The next question we get is, “but what if it doesn’t need curing?” Suffice it to say, animals that normally live in water are largely killed if they’re dried out long enough, and any rock originating from the Pacific indeed fits this category.

Yeah, but Joe Blow said his rock doesn’t really need to cured because it’s cured in Fiji…

Okay, okay…... We’ll go at this yet another way: So you have this rock, and while still in Fiji, all the algaes and sponges have were pulled off, it’s been rinsed of sediment, pampered and coddled to your heart’s content. So now what? It’s boxed up dry for several days, shipped overseas and you put it in your tank. This “pre-cured” rock is supposedly “safe” for your tank. If you’re following so far, you’ll see this for what it is— it’s telling you what you want to hear.

The first person to place Pacific rock in water after importation, will need to cure it. If you’re obtaining rock via mail order, this will most likely be you. If the rock was already tanked in the US for at least several weeks before you got it, the rock should not need curing, but if has not been tanked since it left Fiji it will definitely need curing. Make sense? If not, marvel at this brilliant formula…

H2O animals - H2O for several days
= dead H2O animals.

Remember, this “just imported” rock is still called “pre-cured” or “cured” rock. Doesn’t make much sense does it? Not if your idea if “cured” is rock that won’t produce pollution, and is safe for an inhabited tank. Of course not everything dies during import, not at all, but some loss with resulting pollution is inevitable, and this is the need for “curing”.

But my supplier gets rock that is pre-cured in Fiji…

Hopefully you’ve already figured this one out. Only after the rock gets boxed up and sits dry for several days during transit does it require curing. Nothing that’s done to the rock in Fiji can prevent this. Rock can be taken directly from the ocean and safely be placed into an aquarium providing it didn’t stay out of water too long, but one plane ride across the Pacific and it’s curing time.

But my supplier never has to cure his rock and he gets it directly from Fiji. I guess he buys the “pre cured” rock.

If that’s the case, your dealer must have a private airstrip on a beach in Fiji and uses his own F-16 with an on board holding facility to rush the rock directly to your store. If you suspect this isn’t the case with your dealer, a more likely explanation is your dealer’s holding system is conditioned to handle the massive pollution released from the rock as it’s being produced, so there’s never any rise in pollution as long as it stays there. Put this same rock directly into a normal home size aquarium without massive biological support that’s already accustomed to handle this level of pollution and you’ve just signed up for curing.

To give you an example of this, in a long established commercial rock curing system, one could add lots of “cured in Fiji” (which is now uncured due to import) rock and experience only a minimal rise in ammonia, but if a customer placed this same rock in their home aquarium, ammonia and nitrite would skyrocket quickly. This will happen with any and all Fiji rock that has not been “cured” (i.e., kept in water) for at least a few weeks after import.

But why get cured rock when you can get fresh?

Please tell me I didn’t just hear that? If you still don’t get it, I’m sorry, the nurse will be in shortly to give you your medication…

One more time…

“fresh”, “pre-cured”, rock that has not been kept in water for at least few weeks after import IS NOT SAFE for a tank containing animals.

Rock that has been actually “cured” (i.e., kept in water) for at least a few weeks after import IS SAFE for a tank containing animals.

See the above comments. Some rock takes longer than other to stabilize. Even when added to an established tank, really “fresh” (uncured) rock can easily overload biological support. Don’t look for predictability unless you know your rock is absolutely, positively fully cured. Which brings us to perhaps the most important sentence on this page.

Never add uncured rock to an aquarium containing live animals!

If you’re contemplating setting up a reef tank, or are planning to use live rock in any way, remember this: Adding uncured live rock to an aquarium without an established biological filter conditioned to handle such loads is the equivalent of adding a bucket of rotten seafood with all it’s obviously disastrous results. I can’t tell you how many people I’ve encountered over the years who’ve wiped out entire tanks of animals using the “I’ll just add a little at a time” theory. While it’s possible to get by with adding a “little” at a time, we’re on very shaky ground here, and more often than not, things don’t go as we’d like. If you insist on adding uncured/pre-cured live rock to an established system, be sure the uncured rock is minuscule compared to the rock/biological support the tank already has.