I have three of these (that I can see) that popped up in my tank over the last couple weeks... they look like spider egg sacks - kinda cottony - with what looks like a feather duster popping out the top. But they dont act like feather dusters, they never retract.  Anywho a picture speaks a thousand words:

Cool. Thanks for the ID Marcus!

They are sea squirts.  I type of tunicate and in some tanks they are out of control (not a bad thing).  You know how some tanks have tons of aptasia, or some have tons of coraline algae or tons of xenia.  Well some people have these flourish in their tanks.  I think they are pretty cool, my old tank had quite a few of them. 

Adam

I have thousands of these in my sump and in my overflow.  Never really worried about them as they aren't bothering anything. 

Nice to know what they are though.

Banana Tropics,

I know this question was for Adam, but I will answer it also.  Adam's will follow I am sure.

Tunicates fall under the Phylum Chordata, Subphylum Urochordata.

Most Sea Squirts usually fall under the Class Ascidiacea.

With over 1,000 species of sea squirt it is almost impossible to identify them to Genus or Species (at least for me).

Sorry Jake but I won't answer, because you probably know more about them than I do.

Adam

Jake - get that info from here?:

http://www.biologicall.info/PARTICULAR_BIOLOGY/Superkingdom_Eukaryotae/Kingdom_Animalia/Phylum_Chordata/Subphylum_Tunicates.html - http://www.biologicall.info/PARTICULAR_BIOLOGY/Superkingdom_ Eukaryotae/Kingdom_Animalia/Phylum_Chordata/Subphylum_Tunica tes.html

Pretty interesting, I wondered how something that looked like a sponge could be in the Chordata Phylum.

I've got thousands of these things in my tank.  These and my carribean red fan worms are growing over everything.  Well... the squirts are on the bottoms of everything out of direct light.  If anyone would like a chunk of rock with a couple on it I am doing some experiments with aritifical live rock and have small rocks with this stuff on it.  I'd be happy to send it your way.

- Fuzzy Weasel

Mark Peterson wrote: How can rock be artificial and live at the same time? I'm curious. Please describe.

What makes a rock "live" at all?  It is the bacteria, hitch-hickers, and algae on it.  I'm producing rock using environmentally friendly materials that doesn't affect the chemistry of the tank and grows all of the same goodies that live rock does.  I do know that it grows corraline as well or better.... and I can shape these rocks into whatever I want.  My centerpeice rock is a cave rock about the size of a football with a couple of "shelves" hanging off of it.  It now has corraline covering most of it and has a patch of yellow star polyps that are spreading over to it.

I don't have a working digital camera right now but will be getting one soon... I look forward to posting pics on it.   As far as my research... I am trying to find ways to make the rock more porous and trying to get it the same hardness as natural live rock. The one thing I'll never have is the breath-taking diversity of live that hitch-hikes in on live rock.   But for now I am just wanting to do research on an environmentally safe way to do reef tanks so that I don't contribute to the distruction of some of the most beautiful places on earth.  I'm not an environmental nut, but its my small part.  Besides... these rocks are very neat and fun to make... and my fish love the cave.

If you want to see some more on the artificial rock go to http://www.garf.org - www.garf.org

- Fuzzy Weasel

Yeah... agrocrete.  Sorry if I misunderstood the question.  I am thrilled at the incredible amount of information sharing out there in this hobby.  This message board, garf, and all of the other websites I've soaked up like a sponge. 

And yeah, the agrocrete is LOTS of fun.  Currently trying to find ways to make it more porous and able to grow stuff "inside" of it.  My mix is part oyster and part argonite.  The oyster I get for free all over the place and I also use some local substrate.  (I live in Florida).

What problems have you heard about with it sullying the tank? 

- Fuzzy Weasle

Don't use oyster shell.  Trust me, it is bad.  I stay pretty nuetral on the sand and rock debates, but I don't want people thinking oyster shell is good stuff.  We have had way too many people struggle and fight with their tanks after using it.

I too am glad you like your aragocrete.  I've still never been really impressed with it, and I too have made and purchased LOTS of it.

Adam

" . . . .carribean red fan worms."  Are these what you are refering to?  I have called them Red Cluster Duster Worms.  Pretty cool, huh?  We have not seen our reporducing though.

Yeah, that's them.  And I have a rock that looks to be about the same size as yours.  But the suckers are all over my tank now.  At first they were little white specks on the side of the glass and on EVERY surface in the tank... now those specks are either dieing off or growing big enough to be able to see the unmistakable bright red fan.

It was my LFS that called them "Carribean red fan worms".   I'm beginning to wonder how accurate they are on a ton of stuff.  After doing my research I've noticed several things in their store that are mis-identified.  Not wanting to appear as a know-it-all I don't say anything but it makes me wonder.  Do you know if "Red Cluster Duster Worms" is the proper name?  Or even better... know the scientific name?

Fuzzy Weasel

It think that the local pet store woule be correct in calling them "Carribean red fan worms", IF they came from the Carribean.  They are red and "fan worms".

According to page #138 of Sprung's Invertebrates:

Filogranella species

"Members of these genera form small calcareous tubes 1mm or less and have red or white crowns. They reproduce in aquaria, and can be found on and inside pumps and plumbing, as well as on the undersides of live rock or on the walls of the aquarium or sump. Thick colonies of them sometimes occur on reefs, and they are occasionally harvested from the Caribbean.

Filogranella sp. from the Bahamas. These form calcareous tubes and survive and reproduce in aquariums. They should be maintained in the shade to prevent algae from smothering them, and they prefer moderate laminar water flow."

chrisslc wrote: Hey fuzzy, as for how to create pourousness (sp.?) in the aragocrete, the traditional way to "air-entrain" concrete is to use one of many admixtures for the purpose. But, most of these are detergent based and would pose a threat to a reef of course. you could try mixing in crushed ice at the last moment but the additional water from melting and the cold may effect the setting of the cement directly in contact with the ice. you could possibly grind up parafin wax, mix it in, then boil it out once the cement is set. I wouldn't think leftover wax would be a problem for the tank. I only pose these ideas because it sounds like you're willing to experiment a bit and I'd love to see if it is possible. It would go a long way towards convincing me to use aragocrete before natural rock.

Hey, thanks for the suggestions I will definitely try both.  (am already planning dry ice shavings for the ice because it lasts longer and evaporates without screwing the mix up) This is the prime reason for my new tank... to experiementing with the agro.  I already worked out a deal with my local plastics provider to give me all of the plastic shavings I need.... also worked out a deal with a local seafood store to allow me to pick up as many oyster shells as I want...  and I live near the ocean and am going to try some natural substrate for my mix.   It's going to be a slow process because I am documenting it and following a very controlled research process.  The goal is to have hard fast proof in the end even if it only proves a little.

-Fuzzy Weasel

As I mentioned in another post... Oyster Shells are bad.... very very bad.

Adam

I don't know.  I wouldn't try them, just to be safe, but I don't think anyone has really tried them out.

Adam

Adam, I asked the question without mentioning that I have a large cluster hanging out in the back of my 55 that I put in when I first set it up as a FO. Mostly because I was afraid of that they might be problematic. It seems to be slowly dissolving, so I guess whatever it contains has been leaching into my system for the duration of it's existence. although I haven't noticed any specific ill effects I will say that I haven't had great growth in species that I have seen prosper under similar conditions as mine. but then maybe I'm just looking too hard for a scapegoat instead of buying the MH's I've been putting off. The shells do have considerable coraline growth and provide a good hide out for my smaller damsels, would you remove them in my position?

Mark, that has to be the most simple, brilliant thing I've heard in a long time... cheerios... sheer genius... seriously I'm kinda dumbstruck,it didn't even occur to me but it's perfect.... the dry ice thing might work because freezing doesn't adversely effect early set in cement, it just continues it's cure once thawed, but who wants to buy and handle dry Ice over Cheerios. You can't snack on dry ice while you work. I'm gonna try that this weekend, I've been wanting to make some aragocrete for some time, I even have the setup and materials (no oyster shell), but have always been bothered by the porosity issue.

I really can't equate how valuable this forum is. All kinds of positive and negative exchange and the ability to pick the brains of some highly experienced, helpful people. I've praised it before but I like to encourage things that benefit me so keep posting everybody and thanks