Live rock questions.

[cuttlegirl]

I have been thinking (not always a good idea for me ) about live rock. Is there really a difference in the quality of the rock (Fiji vs. some other place)? Most LFS have different prices based on the origin of the rock (I'm not talking cured vs. uncured).

Also, is there a more environmentally healthy alternative? I know I could get half live rock and then seed the other substrate in my aquarium. I was just thinking about the amount of rubble being removed from the reef ecosystem might impacting the reef in some way. If it is good for our aquarium, it must be helping the reef, right?

Thanks for your thoughts,
Jennifer

 

[Castor]

Also, is there a more environmentally healthy alternative? I know I could get half live rock and then seed the other substrate in my aquarium. I was just thinking about the amount of rubble being removed from the reef ecosystem might impacting the reef in some way. If it is good for our aquarium, it must be helping the reef, right?

Thanks for your thoughts,
Jennifer

Thinking is not the best thing for me to do either I am also looking into live rock harvesting alternatives, and I decided to try to make live rock from agrocrete. I just started the first few batches last weekend, so there is a long way to go. I'm trying to keep good notes, and I'm sure that there'll be quite a few posts from the reef experts. I am not an expert on live rock regions, but I would assume that there is just different micro fauna between the regions. Or it might be economics. Fiji just sounds more exotic, oh well. I'll be glad to know the differences also. Thanks for starting this post!

Felix

 

[mucktopus]

You're right that taking live rock has an impact on the reef. It's a major home to a lot of pygmies and juveniles. It's also used as a construction material for building house foundations all over the tropical Pacific, so it's over-harvested in many (but not all) places. Pieces head-sized and larger are almost totally absent from the easily-accessable parts of the intertidal reef flat where I did my dissertation. Sometimes dugout-fulls of rotting rubble are piled on the side of the path to the village- sitting in the hot sun to dry and bleach. It stinks for ages because of all the stuff dying inside it, including quite a bit of live coral. It has such a major impact on the reef that NGO's have programs to get home-builders to use cement foundations instead. While the aquarium rock might not add up to the same volume as contrsuction rubble, it's kicking the reef while it's down.

Neogonodactylus and students make artificual cavities out of cement mixed with sand. Animals recruit to it in the wild, and it can work in an aquarium once rinsed well and seeded. Live-rock sellers could just make these, put them on the reef flat for a while to seed them with the right flora, and ship them off guilt-free. They could also make them in fun shapes.

Here are the methods from Kate Schaefer's dissertation:
Schafer, K. 2001. The Ecology of an Assemblage of Gonodactylid Stomatopods and Pygmy Octopus in Shallow Sea Grass Beds in Belize, Central America. In: Integrative Biology, pp. 217. Berkeley: University of California.

"Artificial cavities were constructed using a similar method to Steger (1985). Half-liter plastic containers were oiled with vegetable oil and filled with cement to approximately 45 mm in depth. The cement was mixed from coralline sand, cement, and freshwater. Each container was shaken to remove any air bubbles and to flatten the cement. After setting a few minutes, oiled wooden plugs were pressed halfway into the mortar. Each wooden plug was made of two dowels of different diameter; the smaller diameter formed the entrance to the cavity, while the larger diameter formed the bulk of the cavity space. There were two cavity sizes used. The larger cavities had an entrance diameter of 14 mm and length of 5 mm; the cavity diameter was 19 mm and length was 56 mm. The entrance for the smaller cavities was 12 mm in diameter and 5 mm in length; the cavity was 16 mm in diameter and 56 mm in length. After the cement hardened, the surface of the wooden plug and the cement were coated with oil, and additional cement was poured over the top, to within about 20 mm of the top of the plastic container. After the cement had hardened, the two halves of the
cavity were separated and the wooden dowel removed. Using a saw, a groove was cut into the edges of each cavity, perpendicular to the cavity entrance."

 

[DHyslop]

Walt Smith, the primary LR exporter of Fiji, describes the things they do to be more environmentally conscious. This includes having a very large collection area that they circuit over a period of several years to let harvested areas "recharge" before being harvested again. He is also very proud of their facilities to keep the rock live while being held for distribution, and he says he trains their divers not to collect pieces that won't be wanted by distributers.

Given that, I don't know how many of these are valid approaches to sustainability, but he swears up and down that he has extremely little impact on the reef compared to local harvesting for building materials and tourist diveboat anchors.

Dan

 

[William Tyson]

tampa bay saltwater i believe sells aquacultured live rocks, as well as liverocks.com

 

[Andy Lister]

There is a massive difference in the quality of rock obtained from different locations. I work for a large marine importer and wholesaler and we take in a lot of rock.

Fij is without question the best quality rock in the aquarium market, with around 80% coraline algae cover. They are also packed to the brim with all sorts of coral and macro algae as well as lord knows what else.

It really depends what you want your rock for. If you just want it for theaming a tank then you are as well to go for something which is artificial, there are many man made live rock substitutes avilable which are made from clay, newspaper and some other stuff and left in the sea for around 18 months. The encrusting algae cover isn't as good but the shape is faairly nice and I had a rock coated in cassiopea polyps which are now blibbing around my tank as we speak!

Also it's worth looking for the MAC (Marine Aquarium Council) seal of approval on live rock. This can only be bought from a shop which is already MAC certified itself however so it's worth pecking your LFS to become certified!

Anyway. Walt Smith is MAC certfied, which means that all his staff and collection methods have been vetted to standards set out by MAC. As a result he is allowed to sell MAC certified organisms (Or in this case rock) to MAC certified shops.

If you see the MAC stamp on anything then you can be sure that you are getting an environmentally sound piece of marine stuff!

 

[DHyslop]

Thanks for the info, Andy. I had never really looked into detail about MAC and had assumed it was a collector's industry "rubber stamp" organization.

Dan

 

[Nancy]

Tampa Bay Saltwater does aquaculture its rocks and has very interesting descriptions about how they're doing this.

But on the other hand, I was told during my session with the Chesapeake Marine Aquaria Society that many of their members raising corals are making their own live rock in their sumps and prefer to have rock without any of the organisms that come with live rock - no worms, no unexpected critters, etc.

Nancy

 

[Thales]

I'll post at odds with Andy!

The MAC doesn't seem to really have any teeth yet. Once collected items hit the exporter, all the items, certified or not, get mixed with items from other collectors, certified or not. Once those items are exported, they hit wholesalers where they are further mixed with other items, certified or not. And once they hit the LFS, even more mixing happens. So, an LFS MAC certification doesn't really say anything about the the livestock/liverock is certified. And just because an exporter is MAC certified doesn't really mean that what you are getting at the end of the supply chain is actually from that certified collector or exporter.
I really wish I could get behind the MAC, but currently the do very much seem like a rubber stamp organization to me. Perhaps in the future they will be.
If you are interested in more MAC info, the Industry Behind the Hobby forum on reefs.org is chock full of discussion.

Having seen WS's guys collecting live rock in person, I am concerned that their promo doesn't jive with reality - and I really don't buy the idea of a collection 'circuit'. I think all the collectors in the SP say they do it, but I think the reality is very different. From what I heard from locals in Tonga, WS has had just as much negative effect on the environment as any other operation, and that he only cares for promotional value. This is of course, hearsay.

Live rock in general is getting more and more tricky with a lot of it sitting in shipping containers for weeks or months and then being sold as 'live'.

In reef keeping, there are at least a couple schools of thought on live rock. Some people love it, some are worried about bad hitchhikers, some think its almost useless because most of the stuff on it will be rotting due to poor shipping methods.
The Tampa Bay stuff has mixed reviews as well due to where its left in the ocean. The thought is that its loaded with phosphates.
Live rock and its impact on natural reefs is a constant topic of discussion for reefers. You'll get as many opinions as people.

Mucktopus and Andy covered anything else I would otherwise say.

My opinion: buy the rock that you like the look of.

 

[DHyslop]

Thanks, Righty! Your info and views are much appreciated!

Dan