Hidden Cup Coral... allelopathy reading    7/18//09
Good Morning! Love the site. It's very very informative.
<Yawnnnn! Thanks>
I looked through as many FAQ's as I could and used the search but couldn't find much information on my little problem. I have some zoo polyps that haven't opened up for a couple days. I've had them for about 5 months and they've looked great up until about a week ago. I picked up the thin piece of live rock that they all live on and noticed little anemone on the rock.
I've noticed the same thing on a bunch of my live rocks. They are usually closed during the day. When they open at night the biggest one's are about the size of a quarter. They open perfectly round and have white ball tips.
My best guess is that they are hidden cup corals. Are they bad for my tank? Could they be stinging my zoo's?
<Possibly, yes>
My other question is about hydroid digitate. I seem to have a lot of them wisping around the tank. I see them all over at night. Even during the day I can see them.
<These can definitely be bad news>
Based on these two things I'm guessing that my tank has too many nutrients.
The specs on it seem to be okay when I do my tests.
<Mmm, think about this... the available/tested for nutrients could be bound up, scarfed up, by your biota>
Ammonia 0, Nitrate 0, Nitrite 0, Calcium 400, Phosphate 0, PH 8.1. I have a 10 gallon sump and a 55 gallon tank with about 60 lbs of rocks and 3 inches of sand. 2 Nemo's 1 yellow tang, 1 fire/dart fish, 3 green Chromis, 1 peppermint shrimp, 1 cleaner shrimp and 1 algae blenny. Pulsing Xenia, zoo's, GSP, torch coral, leather coral, cabbage coral. 50/50 65 watt Power Compact lights. Aqua C Remora protein skimmer.
I feed twice a day....one meaty meal (flakes) and one veggie meal (sea weed). I have 8 or so different kinds of food. Some are pellets, sinking tablets, flakes, sea weed sheets, formula 2 algae and some live brine sometimes too.
Hope all that detail helps. Any helps you can offer me is greatly appreciated to get rid of the hydroids and the cup corals (if they are bad).
<Mmm, see WWM re Pest Anemones, & Hydroids... and Nutrient Limitation... via the search tool there or the indices themselves on the root/marine web.
Bob Fenner>

Duncans and Clowns, 5/15/09
Hello Crew,
<Hi>
I have a pair of Picasso Clowns and a large colony of Duncans in my tank. Clowns recently ditched their RBTA for the Duncans and beat them up to the point where they only open about half way.
<Happens.>
They refuse to leave them even when RBTA is moved within inches of the colony. Clowns bite fingers etc. , very aggressive about their territory - I know this is normal but isn't an anem preferred over coral typically?.
<Clowns are rarely typical anything.>
I am wondering if there is any method to encourage them to host in the RBTA - so the Duncans can return to normal.
<Only permanent separation most likely, clowns can be very persistent.>
I really like both and don't want to either to have to go. Is this behavior damaging to the Duncans?
<Definitely can be.>
They appear to be fine aside from not fully opening from the constant smothering.
<Stress will take its toll.>
Thanks again,
Cassidy
<Welcome>
<Chris>  

One more Balanophyllia question   1/19/07 I forgot to ask this before.  Would the Giant Balanophyllia eat reef fish (polyps are about 3")? <Can, but unlikely... Most fish species are aware of the possibility and avoid...> Also curious about the larger Dendrophyllia - same question.  We are thinking of getting one but have mandarins and clownfish that have become family pets.    <Again, not a likely issue... there are some Corallimorphs, other families of Scleractinians where there is much more potential...>   Thanks in advance!  You have always been a fantastic source of information!!!   Doug <Thank you. Bob Fenner> Halloween Tubastrea colony... comp.  7/9/06 Hello WWW Crew! <Howdy Brett> I am relatively new to the saltwater and reef hobby (6 months).  Your books and web site have been tremendously useful/educational!  Thank you for your dedication to the hobby! <Welcome> I purchased a Tubastrea micrantha a couple of months ago.  In tank target feeding was not working very well for all of the polyps (some were surviving)  so I switched to the feeding container method mentioned in Calfo's book and on your site with great results.  On the micrantha colony, there also appears to be a small T. coccinea, T. faulkneri or T. aurea  (i.e. an orange sun polyp <Interesting to find these in such close proximity> that I can't identify) polyp growing.  Can these two corals co-exist in the same colony without problems? <Mmm, don't know. They are not found such in the wild though. Occupy different types of habitats. T. micrantha is out in the open, direct currents, the others in more subdued settings out of direct light mostly>   The orange polyp's growth seems to pale in comparison to the black ones.  Has anyone ever seen these corals mixed together in the wild or captivity? <Not I>   The hitchhiker polyp has given me visions of trying to frag together a Halloween mix of Tubastrea colonies with both orange and black polyps.  Do you have any idea if such an experiment has a chance of working or been tried before? <I do not. Am hopeful someone will chime in here... But I'd be asking this same question on the large/r specialty BB's (ReefFrontiers, Reefs.org...)> Thanks for you help and time. Brett Shriver <Bob Fenner> Padoga with small crabs Hi Bob, I just want to thank you for your wonderful site and the help that you have provided me in the past. <You're welcome> I recently purchased a large white pagoda. While viewing my tank last night with a flashlight, I noticed three very small crabs on it. One was only about 3/8 of an inch wide, with it's body only accounting for about a third of that. The other two are within cracks in the coral and can't be more than a half inch wide. They are a light tan color with white claws. Should I try to remove them or are they harmless?  <If there is no apparent damage to your Coral I would leave them be> If I should try to remove them, do you have any idea how I should go about removing the two living within the cracks of the coral? <May seem destructive, but the best approach would be to use a sharp instrument to crush these crustaceans in situ. Leave them alone for now. Bob Fenner> Thank you for any suggestions you may have. -- Mike

Mystery Critter, Hello, I hope you are doing well today. I purchased a Tubastraea sp. after doing much research.  The coral has been doing fine, however there are two creatures living in the rock the coral is on.  Unfortunately, I do not have a picture because the following only happens at night. There are two holes on the rock, each hole has something in it.  You can not notice that the holes are filled with anything, because the skin of the animal is the same color as the rock (there is even a new Tubastrea growing on it), all you notice is a line like a closed mouth on the creature.  At night the mouth opens. and a (feather duster) comes out.. Any idea what these creatures could be? Thanks! Steven O. Garcia ***Hello Steven, First of all, it's pretty much futile for me or anyone else to ID something like this without a picture. If a "feather duster" is coming out then you simply have a feather duster, which are worms of the phylum Annelida, family Sabellidae usually. However from your description I don't think this is the case. What I think you're really seeing is a species of barnacle. Again, I would need a pic to have a real chance of identifying the thing. I'm no expert on barnacle species, but I think I could identify it as such. Regards Jim<<< Sessile invert ID. 9/21/04 Hello, I hope you are doing well today. <I'm great!  Hope you are too.> I purchased a Tubastraea sp. after doing much research.  The coral has been doing fine, however there are two creatures living in the rock the coral is on.  Unfortunately, I do not have a picture because the following only happens at night. There are two holes on the rock, each hole has something in it.  You can not notice that the holes are filled with anything, because the skin of the animal is the same color as the rock (there is even a new Tubastrea growing on it), all you notice is a line like a closed mouth on the creature.  At night the mouth opens. and a (feather duster) comes out..  Any idea what these creatures could be?  Thanks!  Steven O. Garcia  <There are a variety of sessile worms, crustaceans, and snails that fit your description.  All are harmless filter feeders or detritivores.  Enjoy the amazing diversity of life they represent!  Best Regards.  AdamC.> Blenny problems Date: Wed, 9 Feb 2005 Hi, <Hello Chris, James (Salty Dog) here.> I've written to you a few times and you have always promptly replied.  Thanks so much for the help you have given me.  <You're welcome> I am stuck with a new problem, a problem with a bicolor blenny (Ecsenius bicolor) chewing on my Turbinaria peltata. I acquired a magnificent Turbinaria peltata last weekend. Its amazing with light brown polyps and fluorescent green between the polyps. Its been doing great, all polyps expanding. But a few days after I got the coral, I saw patches on the green tissue that looked like someone has taken an eraser and tried to remove the green. I know it was the blenny as he had slight go at my Acro.  He stopped chewing on that now at least. I did not think he would go for the Turbinaria though. I see him sometimes lying in the cup of the coral, all peacefully, then just to turn around and nip a piece of the fresh green tissue. Is this just a phase that will pass, or is it better the blenny goes. <You know Chris, there are some that say the bicolor is reef safe, and there are some that say it will go after corals and the like. So, if it continues, I guess you'll have to give him his discharge.>  I'd rather remove the blenny than lose the amazing coral. If the blenny leaves, will the damaged tissue recover?  <Yes, under good conditions> I want to evict the blenny, and tried a few times to no avail. He's a slimy customer. He has a favorite hole in which he sleeps and hides, and as soon as I get close to the tank with the net..... shwoop, he's gone. I've even tried to coax him out with some food, because he's quite a pig when it comes to food, but that was no good either. Can you suggest a method to remove him easily. I thought of removing the rock in which he sleeps, but I'd rather not rearrange my tank decor if possible. Is there a sort of trap I could build?  <Ahh, the joys of trying to catch a fish in a reef tank. You might try a mantis trap baited with his favorite food. No guarantee, but it is better to try this first that to disrupt the whole system which you will end up doing if he doesn't take the bait. Good luck. James (Salty Dog)>