Sponge?

Re 2: Question...what is this?
Re: What Is This? Possible Snail Egg Collar, Lysmata spp. Compatibility - 2/19/08
Thanks for the quick response!
<Hi Kerstin! You’re very welcome!>
However, that snail doesn't look like any of the ones I have.
<Steeee-rike! That’s one guess down.
You were asking about snails. I have some Astrea, a Mexican, 2 Margarita, 2 Cat's Eye, several Nassarius snails, several Cerith snails, and I think that's it. Most of these are still alive -
<Hmmm, wouldn’t be any of those listed. If you happen to see one of these structures again, do try to get a photo of it asap and we'll take another look. :-)>
I am not replacing hermit crabs because, to reflect the "opportunistic nature" mentioned so often on WWM, <Yep> the last time I added empty shells, they still preferred to get the shell from a live snail vs. a clean shell with no one living in it - an expensive habit to support!
<Yes indeed! I’ve had the same issues with several hermits in one of my tanks. It’s annoying, for sure.>
You seem surprised at the number of shrimp - and the mix. Interestingly enough, I haven't run across anything that indicates how many shrimp one should have on average - and I got the impression that the two types of shrimp would get along well.
<Given enough room and food, they usually do just fine.>
Is there generally a rule on shrimp I should be aware of?
<Nope, there’s no hard and fast rule. It depends on how much food is available, the aquascape (enough hiding areas, etc), and the personalities of the shrimps involved. Basically, as you increase the number of shrimps you have, you increase the competition for food and risk of territorial issues. This is compounded when you increase the number of species involved. I think the four Cleaner Shrimp (given enough food) are fine because they do tend to group together. The Scarlet Shrimp (Lysmata debelius), however, are a separate species and need their own area. Please see this link: http://www.wetwebmedia.com/marine/inverts/arthropoda/shrimp/cleaner.htm >
I am sure my LFS would let me trade some of them back in if I needed to.
<I’d just make sure everyone’s well fed and keep an eye on things for now. As long as they’re all happy in their areas and have enough food, you should be okay.>
Also, r.e. the Specific Gravity - over the past 3-1/2 years, that is what my tank seems to have stabilized at. At one point my 29-gallon tank had around 25 different corals in it (why I upgraded), and it generally moved up to that, even if I worked at lowering it with water changes...should I worry, or just make sure it doesn't go any higher?
<I think you’re fine with it where it is. Mine has been right around the same number for years with no problems. My concern was that it not get a whole lot higher. As long as you’re able to keep it stable where it is, you’re good to go!>
Thanks again for all your help and your fast response,
Kerstin:-)
<You’re very welcome, Kerstin, it was a pleasure :-) Take care, -Lynn>

Re: What Is This? Possible Snail Egg Collar, Lysmata spp. Compatibility - 2/19/08  2/21/08
Wow...fast!
<Heheee!! We aim to please! :-)>
I did actually look at the link you provided...and will keep a watch on the shrimp. So far they seem happy, we'll see how it goes.
<Yep, sounds good.>
R.e. the picture - I actually took the picture the morning it showed up.
<Woops, I thought that it was taken after a few days!>
I had a smaller (only 1/3 of that C) one of these about 1 month ago, when I was at the height of my diatom problem
<Interesting>
(I had the diatom problem because I didn't change my RO filter, and started out with very high silicates; needless to say, it self-propagated the diatom problem until I changed enough water to lower the silicates....lesson learned about filter changes!).
<Yes indeedy! I wish I had a dime for every lesson I’ve learned the hard way!>
I took it out, didn't think about it at the time - but this is the same structure. Could I have somehow imported something with LR? <Is indeed possible.> I have gotten several new ones as I have taken advantage of the new tank to switch out some of my rocks - but I haven't seen any new snails.
<Okay>
Anyway, open to suggestions...you saw in my first email what my LFS was thinking.
<Yes, and I don’t believe any of those are what created this (mainly because of the size/shape). For example, if you had a cucumber/Holothuroid in there that left a casting this size, you’d likely have seen it. I’ve also never seen one leave castings with this consistent "C" shape. Unfortunately, I've checked every source at hand and haven't seen a similar structure anywhere.
What I’d like to know is whether this casting/casing/whatever is rubbery, hard, hollow, etc. I’d like to know what’s under that top layer of sand! Is it a gelatinous/rubbery mass or does it appear to be sand through and through? Is the sand covering a parchment tube? If you blew water at it with a turkey baster, would it disintegrate or would it hold its form? Have any of the shrimp or hermits been picking at it? Sorry, but as you can see, I have more questions than answers. I do love a good puzzle! Unfortunately, at this point, I’m not sure what made this object. Even if you could answer all of the questions I listed above, my answer(s) would still be just supposition. Wouldn’t it be great if we could set up cameras in front of our tanks so that we could see all the neat things that happen when we’re away - and answer some of these perplexing questions!>
Thanks again, and it's fun chatting with you,
Kerstin:-)
<With you as well, Kerstin, it’s been a pleasure. Of course, it’s driving me nuts not being able to solve the puzzle, but hey, the journey’s been fun!

Follow-up: What Is This? Possible Snail Egg Collar – 2/21/08 Hi there again! <Hi there, Kerstin!> Well, I tried to answer some of your questions, and don't know that I succeeded. However, here goes: <Thank you so much! I know I loaded you down with every question I could think of! :-D> 1. I forgot to list 2 other creatures I have in my tank (at least that I know of): a small Blue Tuxedo Urchin, and a small conch (see the attached picture for his size compared to the casing). As far as I can tell, this conch was the only one who ever worked on the casing - and the casing's length was ~3 inches from top to bottom. I have a fair amount of worms in my sand from where I took LS from my DSB in the old tank to this one - but I had never seen this in the old tank. <Okay> 2. The original photo of the casing was taken on Feb. 13; the last photo was this morning (Feb. 21). This morning I also tried to take out the casing, and by this time it was falling apart into pieces, although on Sunday I could still pick it up easily. Without having a microscope, I did not see anything in it this morning other than sand. However, parts of it did feel rubbery - I am sure it was even more so when it was fresh. <Likely so.> I hope that helps <Absolutely, it all helps!> - otherwise, since I seem to have had this before, I will write back if I get another one... <Please do. My best guess is that we’re seeing the remnants of an abandoned tube formed by some sort of tubiculous Polychaete (of which there are many possibilities).> Fig. 1 - left - small conch and the left (disintegrating) side of the casing; Fig 2 - right - the casing after 1 week - looks solid, but falls apart into pieces if picked up. (Pictures taken under actinics only) <Thank you for the additional photos!> Thanks again for all your help, and I hope the weather is better where you are than here, Kerstin :-) (from snowy/icy Kentucky) <Brrrrrr! We’re actually having an unusual stretch of gorgeous weather out here in Seattle. Lol I’ll do my best to send some your way! By the way, you’re very welcome and thank you for the additional information! Take care and stay warm! -Lynn>

Follow-up 2: What Is This? Possible Snail Egg Collar? Sand Clumping? 3/8/08 <Hi Kerstin!> And a cheery good morning (or afternoon). <Thanks, and right back at you!> Apparently this might not have gone through yesterday, so I added another comment... <Thanks, it did indeed go through, and I apologize for the delay in responding! I’ve just been wracking my brain trying to figure out once and for all what these things are.> Well, after our last foray with the unknown, these casings seem to be coming up more regularly - I have two more casings within 3 days of each other (March 4 & 6) - but they're more like the first one I found, not the perfect C shape I wrote about earlier. You had asked several responses ago, and so I picked up the first one (pictured on a towel). It was about 4 cm long, and solid sand - did not feel rubbery, but I also did not look with a microscope as to what might be in it. <That's okay. No need for a microscope!> For what it's worth, if it is of any help, my aquarium contents are (I have been working on making it a full listing): <Thanks, it’s all helpful!> - A 92 gallon tank (moved from a 29 in mid-November), with 1 Purple Tang (Zebrasoma Xanthurum) and 1 Sixline Wrasse (Pseudocheilinus hexataenia) - About 60 pounds of LR, a DSB, and a variety of other critters - 4 skunk cleaner shrimp, 2 blood red shrimp, 1 or 2 peppermint shrimp (they disappeared during the move, have recently reappeared), 3-4 hermit crabs (all that remains), a variety of snails (multiple Astrea, a Mexican, an Olive, <Watch out for Olive snails. They’re predators/scavengers that although pretty, can deplete your sandbed fauna, attack other mollusks.> ..a Tiger cowry, several Nassarius, 2 Ceriths (laid eggs several days ago), a small Conch, and several Margarita, <Sorry, I should have mentioned this before, but these snails (usually Tegula funebralis, Tegula brunnea, or Margarites pupillus) are cooler (to downright cold) water species. Although they’re sold fairly regularly as reef snails, they shouldn’t be. The warmer temperatures in our reef systems greatly shorten their lifespans.> ..a Cat's Eye) and a small blue tuxedo urchin. - My coral collection is 2 Acroporas, 1 Stylophora, a Caulastrea, a Micromussa, 2 Fungia (1 orange, 1 green), a green Favia, an Acanthastrea, and a Lobophyllia. - 2 anemones - Eric identified them as Bunodosoma cavernata…the Warty Sea Anemone - Running a Tunze 9010 skimmer in the tank, also have 3 powerheads - Hydor Koralia 2 and 3, <Love these!> and a MaxiJet 1200. Like I say, I just wanted to let you know that they are still coming up - apparently seemingly regularly, although not necessarily in the perfect C shape. I greatly appreciate any ideas you have...I don't think they hurt anything, it is just a curiosity thing at this point as to what may be creating them. <Heheee! Do I ever understand! I really want to know what these are too, but I don’t see anything in the above list that stands out as a possibility.> Additional comment - I was reading Anthony Calfo's forum on Reef Central, and ran across a mention of aragonite clumping. <It’s interesting that you should bring this up. I've been wondering whether it was possible that these formations were aided/created by a snail or urchin and clumping action. In other words, in the course of its foraging/burrowing, one of these critters plowed up an area of sand that had on the surface, something sticky enough (mucus, bacteria, etc) to hold the top layer together and roll it into these forms. Any thoughts, Bob?> A quote from Dr. Ron Shimek was: "Here is what Dr Ron has to say on the subject http://www.reefcentral.com/forums/s...hlight=concrete quote: Originally posted by Dr Ron Many aquaria are saturated with dissolved mineral salts such as magnesium and calcium carbonates. In the sand bed where water flow is slow and the chemical milieu is different than in the water column, precipitation of calcium salts can cause clumping. The high pH environment you mention facilitates this clumping. In essence, in such a situation what is created is a type calcareous sandstone. The other cause is clumping due to bacterial cementation. The bacteria in the sand bed glue the grains together with a material referred to as a glycoprotein; basically this is a material about the consistence of rock candy. Once the bacteria have bound the sediment, the minerals can also precipitate and make the binding permanent. When one inoculates a sand bed, one needs to strive for maximum diversity of the burrowing infauna. The action of these small animals will keep the sediment rather continuously in motion and prevent the cementation. In addition to the lack of these "motivators" of sediment motion, the larger sediment particles tend to resist movement, and consequently facilitate the cementation." So to check, I also want to say I have the following measurements (after a 10 gallon water change done just earlier today, using SeaChem's Reef Salt): Calcium around 300, Alkalinity at 2.06. mEq/L. :-( Apparently over the course of the last month it went from both values being high to now both being low...so I will work on correcting them, <Good, just take it slowly.> ..but that means this isn't a possibility for the clumps, and we're back at square 1, right? <Hmmmm, well clumping can be caused by a number of things, pH problems, not enough water flow, lack of adequate sandbed fauna, overcorrection of calcium, etc. You might want to stir the top layer (~1/2”) of sand and see what happens (look for sticking or clumping). Please search the term “clumping” at WWM for more information: http://www.wetwebmedia.com/WWMAdminSubWebIndex/question_page.htm> Thanks again for any input you can provide, and I hope you're having a nice and warm day, Kerstin:-) <You're very welcome! So far, so good on this end as far as weather goes. Hopefully the new winter storm they predicted for y’all never happened and that you're nice and toasty! Take care, -Lynn> IMG_6924.JPG On a towel IMG_6932.JPG Same size, in tank under MH with flicker

Follow-up 3: What Is This? Possible Snail Egg Collar? Sand Clumping? 3/8/08 <Hi Kerstin!> Thanks for the great response. <You’re most welcome. I just wish I had a concrete answer for you!> I will keep searching on "clumping". <Sounds good. I have my doubts as to whether that’s really what’s causing the formations, but it’s something to consider/rule out.> I thought I had pretty good water flow (~1750 gph + my skimmer), and before I sold my 29-gallon tank, I got about 1-1/2 cups sand from it, so my sandbed seems pretty well along. <Good> Re: the Margarita snail - yes, I bought it before I researched - and this point I will let them survive until their death, but will not be replacing them...and feel bad for shortening their life, in fact. <Yes, it's sad, isn't it. I doubt there’s an aquarist out there that hasn’t made a similar misstep at some point, and felt horrible about the inevitable result. I know I have. Complicating matters is the fact that these snails are often sold as part of reef-cleaning packages. People are led to believe that the various animals included are well suited to reef systems. It’s a very unfortunate practice and I’m going to stop right there before I get on a roll! Suffice it to say, experiences like this serve to teach us all a sad but valuable lesson.> Thanks again for all your help. We did end up getting about 5 inches of snow - but it's nice, and once the drive is shoveled, it melts pretty fast...so it's not all bad. <Oh good! LOL I wish you could send some out here. I’m one of those crazy people that loves snow!> Thanks again for your help and this great website, Kerstin:-) <You’re very welcome, Kerstin, and thank you - it’s been a pleasure! Have a great weekend, -Lynn>

Follow-up 4: What Is This? Possible Snail Egg Collar? Sand Clumping? Nope! 3/8/08 3/10/08
Hi again!
<Hi there, Kerstin!>
Well, I have continued searching, and you know that looking for people who have written in about worm poop or castings or sand being compacted...well, I seem to be the first one...or I am just not searching the right words.
<This has been quite a challenge, hasn’t it!>
In any case, since Dr. Shimek had mentioned sand being "concrete", I submitted my query to him as well, and his response was:
"Your structures appears to be fecal castings (= "used food" ) of a deposit (= sediment) eating large worm or sea cucumber. It is definitely not a snail egg collar, very much the wrong shape and "texture." "
<Yes, although the initial photo did remind me of a sand collar/egg casing from a Moon snail, the subsequent photos did not.>
That made me think it must be a huge worm (!), which I asked about (esp. since I have not knowingly purchased or imported one into my tank); in return, he responded:
"These animals are occasionally found as hitchhikers, and they come in as small individuals and may grow in the tank. It is likely it is living in your sand buried out of sight. Such creatures are good additions to a tank; as long as it can get enough food, it will be a good detritus-feeding animal.
You may never see it, even with staying up at night looking for it. Such worms typically live their entire lives under the surface of the sediments, and just back up to the surface, stick their anus out of the sand a bit and defecate the fecal casting. My guess is that this is happening far more frequently than you realize, probably once a
night or so. I suspect most of the time fish, other animals, or currents disperse the sand before you observe it. "
I hope that information is useful to someone else out there as well...I think it's also interesting that something as big as this possible worm could be hiding in my DSB. Personally I still like the idea of egg casings - there are some neat ones out there, that I could find pictures of - but don't you know, that would have been too simple
an answer. :-))
<Heheeee – too true! I’m so glad you were able to have this answered! This does indeed help me, as well other aquarists with similar castings showing up in their tanks! I too would love to see the critter that’s leaving poo of this size! The reason I discounted the possibility originally was that since the sand/substrate had been transferred from one tank to another, it seemed unlikely that such a sizeable worm, or Cuke, would go unnoticed. Ah well, maybe it was hiding within some rock, etc, that was also transferred/introduced. The point is that I implicitly trust Dr. Shimek’s judgment in these things and am relieved to finally have this mystery solved for you! Yay! By the way, if you ever do see this critter out an about, please let us know!>
Thank you again for all of your help - I really appreciate it, and all the work you did researching about this. It's been fun talking about this, and hopefully someone else will be able to use the information as well.
<Absolutely! You’re very welcome and thank you as well! It’s been a fun learning experience and I know the information will be very helpful to others.>
Also (shameless plug) because of all the help you and everyone at WWM have provided, I did make another donation - I think something this great should be considered in the same light as shareware - it will improve and continue to be there for everyone who needs it if people have it in their hearts to consider what it is worth to them...
<Awww, that’s so kind of you! On behalf of Bob and the rest of the crew, a most sincere thank you! :-)>
Kerstin:-)
<This has been a real pleasure, Kerstin! Take care, -Lynn>

Please help ID these...Eggs?   2/19/08
Good Day! I am a Long-time reader and 1st time writer! I hope you can help me as I've witnessed you help millions!
We have a 16G Bow front Display FOWLR tank (actually we have a few Paly's and Mushrooms in there) w/ 2 True Perculas and 1 Citron Goby. There are plenty of snails, crabs and even an Urchin. I have seen many fire/bristleworms, spaghetti worms, pods and feather dusters.
Parameters are:
Nitrite: 0
Nitrate: <15
Ammonia: 0
Salinity: 1.024
Temp: 79 degrees
Calcium is normal and Phosphates/Silicates are in check
We woke up this morning and found these little brown things everywhere! They look like little pieces of dirt, but appear to be eggs. There was a large snail that was in the area of these and may be the culprit.
<I do believe so...>
I have had Nassarius snail eggs before and they looked nothing like these! I hope the picture helps.
My question is what are they, will they last and are they good??
<Might otherwise be urchin eggs... likely will be consumed... Are "good"... not toxic>
Any help would be appreciated. Thanks in advance and keep up the good work!
Derek L. Rush
<We're trying! Bob Fenner>

Re: Please help ID these... Eggs?
Thanks for the quick response!!! It's an honor to be answered by the one and only Mr. Bob Fenner!!!
Anyways, someone told me that the things I see are just harmless pieces of Urchin Pooh!
<Heee! Could be this as well... There are some snails that do lay eggs that are quite similar though (as well as the more familiar clusters by some species found arrayed on viewing panels, and in webbed clusters attached to hard substrates...)>
If that is true I was wondering 2 things:
1) Will this cause a rise in Nitrates?
<Mmm, not likely appreciably>
2) I've heard that Urchin feces carries Coralline Algae spores? Is that true?
<Likely so... digested to some extent>
Thanks again and I will be looking forward to your response!
Derek L. Rush
<BobF>