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All My Polyps are Closed!!? Anomalous Xeniid
Xenia hlth. issues -- 11/17/2009
Xeniid system/health Q's 3/19/07 Thanks so much for the advice. <I welcome you to our help in Bob's stead. GrahamT here.> <Heeeee! Welcome yourself! RMF> I will keep watching. I wonder if I could bother you with one or two more issues. <Well... I... guess so.> I cannot keep xenia. <You aren't alone, my friend. Many have problems with this coral. http://www.wetwebmedia.com/xeniidfaqs3.htm > I know you have heard it before but I am determined. <Good.> I keep trading Starpolyps for small pieces and came across some info I questioned. I understood xenia to be one of the few (if any others) that do not participate in chemical warfare. <Well, they participate, just usually on the receiving end. As I understand it, they don't broadcast their chemicals into the water column as most other warring parties do. They can still kill by direct contact, though. There are some good pieces available on the internet that document the war between soft and stony corals. There are very many more and better catalogued pieces at a nice library.> the piece I saw in Reef.com said they kill off Acropora easily. Can you clear that up. <Just did, oops. See above.> Each time I add xenia it seems fine for the first 24 hours and then condenses to solid white polyps. My non-pulsing anthelia is reproducing and my xenia keeps turning into balls. <Mmm, this is a clue, methinks. Anthelia is winning the one-sided war.> I keep playing with alkalinity and salinity making sure the rest of the reef does no suffer. <There are those that swear by Xenia's need for iodine to thrive. I think that your water changes probably maintain high enough levels of iodine so that this is probably not the issue. I would consider adding some fresh carbon to the system and trying a small piece of xenia upstream (as it were) from the anthelia, though not in direct current. Sound do-able?> Do you have any suggestions for me? <Umm, yeah. (See above)> thanks Cathy <-GrahamT>
Dead Xenia 1/3/07 I am new to this site and have read much of your excellent info. <Welcome! Glad you found us! Mich with you today.> I'm hoping someone can help me out with a minor disaster currently happening in my tank. <Minor disaster...jumbo shrimp...oxymoron?> I have had a pulsing Xenia for about 1 month that was doing very well. <OK.> Overnight, it crashed and never recovered (PH was good during the day, did not test after extended darkness though) As soon as the Xenia started to go south, both of my shrimp (cleaner and peppermint) died. <Likely something else caused the death of all three.> My fish all seem fine, water levels are fine, and polyps are fine. <These organisms may be more tolerant to whatever took out the Xenia and the shrimp.> I have a 100 gallon with 330 watts of light. Could the Xenia have emitted something toxic that affected the shrimp? <Again, unlikely. Xenia is a good bioassay organism in that it will warn you of a problem by promptly dying, sort of like a canary in a coal mine.> Any help would be greatly appreciated as I'd really like to have Xenia again. <Sounds like a potential contamination event. Source could have been internal or external to the system. Is there anything missing from your system other than the Xenia and the shrimp? Did anyone in the household "help out" by wiping the walls of the tank down with a cleaner such as Windex? I would review your recent activities around the tank... this may help identify the source of the problem. I think you should be able to keep Xenia at some point in the future, but I would not add Xenia for a while.> minus the melting. <Yes, not pretty, ...and even worse smelling!> Thanks! <Welcome and good luck! -Mich>
About Xenia... dis., comp. 8/23/06 I
having problems to keep any species of xenia in my reef tank. I would
like someone advanced aquarists to help me solve the problem.
I tried to keep a lots of different species xenia but no
one can success. Water quality? <Possibly> Lighting? <Not
likely> Water movement? <Could be> Nutrients? PH? I do
everything but did not see the result. Still cannot keep xenia in my
reef tank. My tank size:
36"x18"x18" with 15gallons sump with feather
Caulerpa filter with 24hrs daylight lighting. with Plenum and 4"
2mm sand bed. 20kg live rock in main tank.
equipments: 1 (Eheim) return pump 3396l/hr
2 (Seio) water movement pumps 2400/hr 1
(Aquanic) water movement pump 1500/hr 1 (AquaMedic) Skimmer
with pump 2500L/hr 1 280watts chiller
This is my tank water parameter:
8.3 Ammonia - 0mg/L
Nitrite - 0mg/L
Total Nitrate - 20mg/L <A bit high... would keep no more
than half this> Phosphate - 0mg/L
11-12dKH salinity - 1.0235
<Better near 1.025> Temperature - 26.5C
Calcium - 450mg/L
Magnesium - 1300mg/L
* I use SeaChem Reef Plus twice a week to maintain the
iodine and trace element, and Kalkwasser to makeup water.
<Might be something in how you're
administering these last two> Lighting: 1
14k T5 1 Actinic T5 1
12k fluorescent (sera) 2 actinic fluorescents
(Acadia) Fishes: 1 yellow
tang 1 blue hippo tang 2 clown fish
3 green Chromis 1 Sixline wrasse 1
flasher wrasse others: 2
cleaner shrimps 1 blue legged hermit crab
corals: LPSs: 1 open brain, 1 green galaxy.
soft coral : yellow polyps, different species buttons and
different types of mushrooms. <Very likely
allelopathy with these other cnidarians> Problem:
- every time I added new xenia into my tank the xenia not
open sometime will melted within 2days. - sometime the
xenia looks unhappy and dry look then slowly die off. -then
I tried to buy the established xenia from the LFS. the polyps open very
nice in the LFS established reef tank with only actinic light.
<Don't need actinic...> When I put it in my tank 1st day
still open but not like at the LFS. 2nd day the polyps open bigger then
1st day. 3rd and 4th day looks good polyps open nicely, but till 5th
day it looks unhappy the polyps looks dry again.....:( is no reason
every things is ok but only xenia. I really loves this coral but very
hard to keep :( why? why? why? - others coral in my tank
doing very well and spreading very fast like button. Maybe I got no
luck with xenia :( Steve xxxxx <Mmm...
I would try adding whatever Xeniid to a separate "go-between"
tank, with only partial water from your system, the rest all new...
adding some more tank water weekly... Please read on WWM re Pulsing
Corals: http://www.wetwebmedia.com/xeniidarts.htm and the linked files
above, as well as searching, reading re the terms mentioned above. Bob
Xenia and Yellow Polyps...Health 5/16/06 Bob: <James with you today.> I'm a new salt water/reef enthusiast. I only started three months ago with two tanks... a 20 gallon and a 55 gallon. I have CoralLife Compact Florescence with dual tubes @ 65 watts (Dual Day Light 6700K/10000K and dual Actinic 420nm/460 nm). I have moderate to heavy water flow. I keep pH higher than 8.0, Specific Gravity around 1.025, temperature at 78 F, keep my Copper below 0.25 ppm (one tank is zero, one tank has trace from when I introduced a Blue Tang that had copper medication on it), Ammonia = Zero, Nitrites = Zero and Nitrates > 40 ppm. I provide Iodine, calcium, vitamins and adjust pH with Carbonates. I have had great success with fish, crabs, shrimp and some invertebrates (urchins). I introduced a yellow polyp about three weeks ago and it was doing well until this week when it did not seem to open anymore. I feed them twice a week by squirting with a medicine dropper with commercial phytoplankton. Since they stopped opening, I squirt them once or twice a day. They seem to have lost some individual polyps, but they seem to be retracting rather than growing. They are also darker in color....when I got them they were light yellow, now, they are brownish yellow. Is this the end for them? Last Sunday, I purchased a Xenia from a local store that is 45 miles away. I have read that Xenias do not do well in transit so I elected to get it from this store. They do not have guarantees so I picked up one (they said that the coral was mounted only two weeks ago). They packed them in a double bag but were not very careful about not "crushing" the coral. When we got home, the coral was "under the rock". I acclimated it overnight (in the dark). This morning, the Xenia looks contracted and no movement whatsoever. There were pieces of it on the surrounding rock (like white spots and some small tissues). Can you provide some insights as to what is going on. My understanding is that Xenias do not need to be fed, that they are totally photosynthetic. I appreciate anything you can help me with. <First question before we go any further. Is the coral in the tank you are getting a copper reading from? If so, I believe that is your problem. James (Salty Dog)> Noli
Xenia detaching 2/9/05 I really appreciated the website. I use it extensively. I bought a lovely piece of rock with three large Xenia stalks. They have been pumping and waving about and are quite beautiful. A few days ago I notice that one of them seemed to have a break in the stalk and this morning it had broken off altogether and was lying on the substrate, still pumping. <Many possible reasons... not excluding a shrimp, crab or fish clipping it off> I replaced it in a crevice in the live rock hoping it would reattach since it still seems to be alive. Now today I notice that the largest of the remaining two stalks seems to be detaching itself and I fear the same fate for him. <hmmm...> Other than that they seem quite healthy. I have searched the website and most of the questions seem to be about them not pumping or lesions or retracting/melting. I don't seem to find anything on them breaking off or detaching. Any words of wisdom? <Since they are still pulsing and re-attaching, it sounds like some creature is disturbing them... do watch at night with a red light> Also, I'd like to keep my pod population from being decimated but I don't have a sump. You suggested a pod cultivating kit but the website didn't give much information other than advertising a bottle of liquid pods, can't remember the name of it. <Without a refugium, you are mostly resigned to adding bottled supplements at times. Oceanpods.com or Seapods.com> Is it just a supplement you add to the tank or is it something you have to have refugium for? thanks for your help. Janie <Live cultures to boost your tank. Anthony :)>
Xenia Woes 8/2/04 Hi, I've been an avid reader of your forums, and CMA, and I would like to say what a great source of info!! Any problems I have had so far, the forum has cleared, but I'm stumped with my xenia. <lets have at it! Tally ho> First a few tank facts: Its 34 gallons a 3 gallon sump where I have a DIY Schuran Jetskim 100. <fantastic> In the sump I also have a bag of activated carbon. <do change small amounts of carbon weekly instead of large amounts monthly for best results> Water movement is created by an Eheim powerhead, and I also have a Fluval 304 serving as extra bio filtration. The Fluval is connected to a spray bar that creates a great current in the tank. Lighting consists of 2 x 20 Watt 18000 Kelvin fluorescents and an extra 20 watt actinic, making a total of 60 watts. <this is extremely low for keeping cnidarians animals (corals/anemones). Waayyy too much blue light here. The blue is used mostly for aesthetics. A general rule of thumb is a minimum of 5 watts per gallon of daylight for reef corals. And of the 40 watts of non-actinic here, they are not only 110 watts shy of the mark, but also too heavy in blue (as 18k K) themselves. Zooxanthellate corals and polyps will slowly starve to death under these lights> Water temp tends to be around 24.8, but warm weather drives it up to 26. Ammonia 0 Nitrite 0 Nitrate 10mg/l Calcium 320 mg/l Alkalinity 12dKH Salinity 1.023 <allow the ALK to fall to around 10dKH and then push the Ca up towards 400 ppm (no higher needed) for better results> pH (lab tested 7 hours after lights were off, so "night" time) 8.2 <very fine> I dose daily iodine, and weekly I dose with tropic Marin pro-coral elements, so called 70 trace elements to cover all needs. Livestock are: maroon clown, bicolor blenny, <Hmm... do be very careful here: blennies in general are not at all reef safe. They are nibblers on coral> six-line wrasse, 4 turbo snails, 5 blue leg hermits, 2 lumps of Palythoa, and 2 mushrooms, decrepit xenia. So that's about it. My problem is that my xenia does not seem to open. It stays shriveled, and is very slowly dissolving away. I did a water change to see if things would improve, but no luck. All the other animals are very happy, the hermits are even molting, and I've never seen the mushrooms so expanded. <the mushrooms are actually panning for light. A very conspicuous sign of low light here> The xenia is in bright light all the time. But the funny thing is that, there are a few pieces of loose xenia polyps around the tank, out of the main light and they seem fine, <variable tolerance... all will suffer in time> just the large clumps stay closed. Also another question, does the bicolor blenny feed on xenia, because, I can't find a culprit, but it might be that the blenny nips the xenia then it is closed. <very possible> What could be the problem, I know my calcium is a bit low, so I will try and increase that, but it must be another problem! <true... no biggie> Please help, Thanks Chris Browning <best regards my friend, Anthony>
Xenia health, survival I have tried to grow Xenia in the past but without much luck because of an overly aggressive Coral Beauty and Maroon Clown. I sold the fish and now I am in the process of trying Xenia again. This time the Xenia (silver branch) did spread from the rock it was on to the rock placed next to it (some splitting did occur on a few of the corals). That's all that happened. Then after a period of time (1-2 weeks the base of the Xenia began to turn white and eventually it dissolved. <many possible reasons for this my friend... most common are low or flat pH or ALK (under 8.3 and/or much under 10 dKH)... and aggression from other corals. Xeniids are weakly aggressive> Amazingly I have had good success growing both hard and soft corals of all varieties. The corals I currently have include torch and frogspawn, several varieties of mushroom coral, star polyps, button polyps, leather coral and others. <yikes... you just names most of the top 10 most aggressive corals <G>. Seriously, your Xenia could be suffering from this unnatural and aggressive "garden reef" mix of corals. Do a keyword search of our website from the index page wetwebmedia.com for "garden reef" or "allelopathy" to see FAQs on similar challenges> Everything is reproducing but the Xenia. My tank parameters are: 90 gal show + 50 gal (20 gal overflow holding and 30 gal refugium) 440 watts of VHO (220 actinic, 220 aqua sun) on the 90 gallon CPR Protein Skimmer Calcium + 450ppm <hmmm if this Calcium is an accurate reading, it is on the high end unnecessarily IMO... do be careful .> Specific Gravity 1.023 - 1.025 Temperature 76 - 78 degrees Alkalinity 3.2 mg/l Ammonia 0 Nitrate 0 <you can allow some nitrates to linger to help feed corals/Zooxanthellae... 5-10ppm is fine> Nitrite 0 PH 8.2 - 8.4 <if this is a daytime reading, do check to see how low your pH goes at night. No problem here... but do try to make a habit of maintaining 8.3 for a minimum round the clock> I test for PH, Alkalinity, Calcium and Specific Gravity on a weekly basis. In addition to adding calcium and a buffer I generally add trace elements and phytoplankton when I perform water changes (weekly). <you have listed no corals above except maybe the leather in tiny amounts that will eat phytoplankton... do focus more on providing zooplankton as the vast majority of corals are carnivores> However I haven't added trace elements or phytoplankton for several weeks as I was being cautious of over dosing and starting a micro algae growth problem. <yes... very good/wise and correct> I have a bunch of macro algae that is growing like crazy in my refugium. I don't use any charcoal for filtration. In fact my filtration consists of a protein skimmer, macro algae and floss to catch debris before sending the water back to the aquarium. The tank has been set up for a little more than 2 years. <all good> Any ideas of what is happening? <perhaps the tank is mature enough and simply has too many aggressive competitors. Its really a lot for such a small volume of water> I really like the looks of the Xenia and want it to grow but so far not much luck. <do try establishing it in a refugium instead. They will pose no burden on plankton as they cannot eat organismally> Any help is appreciated, Craig Walker <best regards, Anthony>
Dying Xenia 4/28/04 I tried putting this on the
911 site Saturday. I kind of wrote it
wrong. Where I put Iodine below I put ammonia by accident.
Anyway, here is the problem: My pulsating branch Xenia is not looking
good at all. I really need some help. I have read several Q and A's
on this site about Xenia problems and how to fix. I have tried
everything. It looks like he is melting. He was doing great for 5
months until then. It started last Sunday when I did a water change.
The only thing I did differently this day was I did the water change
with R/O DI water for the first time instead of dechlorinated tap water
(had a brand new one of these delivered to me last Saturday). Made sure
my measurements matched the tank before I put it in. Measurements in
tank Amm 0, nitrite 0, Nitrate 10, PH 8.3 SG 1.025, temp 78, calcium
350. <all good> Been putting iodine in every night as I always
have, I moved him about 12" away from a green star polyp coral in
my tank to see if that would help (he was about 8" away prior).
<indeed... green star polyp is extremely aggressive (chemically
noxious as well)> I have put in a Poly Filter since then to see if
that would help (I always use carbon also). I have not put anything new
in the tank and I can't see any marks on him either. If I can't
find the problem soon he will probably die. Any help will be
appreciated. Thanks, Tom <when in doubt... do a(nother)
water change. And with Xenia... focus sharply on pH. If 8.3 is your
daytime pH... then your pH is too low. Many Xenia stress below 8.3
which is occurring after your lights go out (aim for 8.4-8.6 by day and
no lower than 8.3 by night... use Kalkwasser to help achieve this). Do
consider and try. Best of luck, Anthony>
Melting Xeniids & Flatworms Galore Hi there WWM Crew. <Hey, Mike G with you tonight> Have been enjoying your site and links but have run into a couple of problems. To begin, let me give you the stats on the tank: <I personally thank you for giving me the stats on your tank. Out of many, many emails I have answered today, you are the first to provide such information. :-) > SG 1.025 <Fine> pH 8.0 in the morning (before lights come on) and 8.2 5 hours after lights on.. <You might want to find a way to remedy this. That is a large pH swing, and would cause undue stress to your pets.> NO2 (0) <Perfect> NO3 (20) <Okay, but it could be a bit lower> NH3 (0) <Perfect> Tank is set up with l MH l4000K and 2 65W 03 actinic along with a Bak Pak 2R protein skimmer that's skimming l/2 C of green stuff a day. Tank temp. fluctuates between 77.5 to 80F degrees lately. Water change weekly 15 gals. Sometimes time doesn't permit, and water gets changed every 2 weeks. <Sounds fine. I am left wondering how large your tank is, though.> Problem l: For some reason, my pulsing xenias are dying (melting) and I can't figure out why. Have had these Xenias now for almost 2 years pulsing and dividing away and now... What's going on here? <This is a common problem with Xeniid corals, they seem to "melt" when in unfavorable conditions or after drastic changes in water parameters. Take a gander at the following link, namely the topic "Xenia Health" about 3/4 down the page. http://www.wetwebmedia.com/xeniidfaqs3.htm > Problem 2: My frog spawn frag (originally only 2 heads - now 6 heads) has been invaded with oval shaped pumpkin colored flatworms - have no idea where they came from as I do quarantine any and all going into the main tank. I've read that they come and go But, now they've migrated to my pagoda coral and I really don't want it to take over the whole tank (60 gal)! <Ah, there we go, 60 gallons. Flatworms have a habit of overrunning marine aquaria.> On my next water change or sooner, can I do a fresh water dip or Lugol's iodine dip on these two corals without harming them and hopefully getting rid of the flatworms? <That is exactly what I would have recommended you do.> Thank you for your help/advice. <Best of luck, Mike G>
Save the Xenia? - 8/28/03 Hello, I've been having a problem with my xenia. When I first received it, the original xenia colony grew and spread rapidly throughout the tank (and was pulsing). However, over the last month, the xenia has slowly stopped pulsing, no longer extends, and even the small brown polyps at the ends of the stalks look like they are deteriorating. <predation or water quality likely> The main xenia stalks have completely shrunken and now all that's left are the individual stalks. The strange part is that everything else in the tank seems to be doing quite well (leather, gorgonian, many mushrooms and polyps) <actually... the four Cnidarian groups you just mentioned easily make the top 20 list of most aggressive corals regarding noxious exudations. Your Xenia may very well be suffering from their aggression if your water change schedule and or chemical filtration has been light. Weekly water changes and small weekly/monthly changes of carbon are ideal> and I've gotten coralline algae growing on the live rock and back of tank. <not a fair comparison... these are all completely unrelated organisms with different tolerances> I realize xenia require phytoplankton/light/iodine - I've recently started adding DT's (the problem started at least 1 month before this, though), Seachem reef iodide, there are 2 x 96 W power compacts (6500 and actinic O3). <you are mistaken my friend... Xenia cannot even eat phytoplankton. They do not have fully formed digestive systems to eat organismal prey. In fact, they are one of the closest corals to being autotrophic as it gets... getting all they need from light and feeding by absorption> SG is 1.021-1.022. <hmmm... the salinity is a little low. For coral keeping, please do stay at full strength seawater 1.024-1.026. A dilution in turn dilutes coral sustenance> Recently I've seen a white powder that doesn't dissolve when I make up new water w/ instant ocean (didn't see this a few months ago when the bag of salt was opened). I also was trying to raise Ca2+ last month w/ Kalk and Seachem calcium-gluconate, and also have used B-ionic. I've also been doing 5 g water changes (30g tank) every 2-3 wks. Any suggestions for saving the xenia? <if the problem is not predation (tiny worms, snails etc).. then look at your pH and ALK. Xenia are very strict about high pH. Daytime readings should be *.4 or higher... and watch that night/morning readings do not dip below 8.3 (they will often stop pulsing like clockwork). Alk should be in the range of 8-12 dKH (preferably towards the higher end. Ca will be fine at a modest 350-400 ppm> Thanks for any advice. Ben <please take the time to read through our archives on this subject. Go to the main page www.wetwebmedia.com and type in Xenia into the Google search tool for our site at the bottom of the page. Best regards, Anthony>
Xenia Health Hello, I have had xenia flourishing in my tank for over six months and have shared many frags with others. <very good to hear...especially the sharing part <G>> Three days ago, I noticed that several of the stalks have what appears to be some sort of injury...looks like some sort of wound with this crusty yellowish stuff. <Hmmm.... caution here. Can be rapidly infectious> The affected stalks appear to be dying and several more stalks look to be in peril each day. I have seen xenia crash or "melt down" in other tanks (as it seems to be famous for) but this is very different. I have tried to see if any of the tank mates are bothering the xenia but I don't see any. Everything else in the tank is as happy as ever. Any ideas? Thanks kindly, Jonathan Bush <yep... they are quite sensitive to water quality. A dip below 8.3 in pH or very low ALK (below 8 dKH) is often the culprit. Also lack of water changes and Iodine supplementation (colony reaches critical mass as nutrients are depleted with growth). And lastly... chemical burns from the accumulation of noxious allelopathic compounds in the water from aggressive corals (star polyps, mushrooms, colt coral, etc). Weekly carbon changes in stead of monthly, aggressive skimming, PolyFilters here for this. Best regards, Anthony> Jonathan Bush
Xenia Lost Their Zip! Hi Guys <Scott F. your guy tonight> I have Pulse Xenia and white star and some metallic green xenia all other corals bubbles, leathers and other polyps are quite happy. But the Xenia never seem to grow and the pulse stays contracted but still pulse? The green xenia looks like it may be dying off. Water quality is fine ,will additional strontium help? <I have not heard of strontium supplementation being beneficial to this species...> or am I missing something else? Thanks, Tim <Well, Tim- there are all sorts of theories as to what makes Xenia pulse. Some hobbyists swear that iodine supplementation is the key, others feel that light and current play a bigger role in this "behaviour". A valid theory is that Xenia tend to pulse at steady, higher pH. Xenia are thought to be autotrophic, meaning that they don't generally require supplemental feeding. What you need to do is to review your tank's parameters once again, checking that pH. Perhaps you are positioning your Xenia near other, more aggressive corals, and they are becoming victims of "allelopathy" (chemical "warfare")? You certainly could experiment with iodine- but do test for anything that you should add. Do pick up a copy of Anthony Calfo's "Book of Coral Propagation" for a thorough review of the care and propagation of Xeniids. Do a little research- you should be successful! Regards, Scott F.>
Xenia is dying Can you please help? I have a 150
reef tank. It's been set up about 2 years. I put in 2 or 3 pieces
of xenia more than a year ago. It has grown and speed like wildfire.
All of a sudden, they are turning white and shriveling up. Any ideas?
<many possible reasons for this but far and away the most common is
a low pH. Xenia are notoriously sensitive to low pH. They stop pulsing
at 8.3 and really show suffrage under 8.0. A reef aquarium ideally (to
me) does not drop below 8.3 at night (low point).> Thanks, Ricky
Knapik New Orleans, LA <best regards, Anthony>
A Non-Pulsing Xenia Hi there, I bought a White pulsing xenia last week. When I placed it in the tank it looked ok and pulsed like crazy. But at about 3 days I noticed that the middle stalk was rotting so I removed it by cutting the middle portion and left me 2 stalks that are still alive. <Smart move> Since then the my xenia's just stopped pulsing and is turning into a light pink color. Sometimes it pulses but very weak compared to when I first got it. The polyps are open but is thinner than before. What could be the problem? <A whole bunch of possibilities; iodine, low pH, low ORP, current, lighting, or temperature differences/problems.> Thanks <Sorry I could not be move definitive. -Steven Pro>
Xenia rash ??Dear Mr. Fenner, I am writing you again to pick your brain. Question 1: I have a 125G Reef tank which is about 5 months old. I purchased several "generic" Pulsing Xenia in the beginning of the reef. I now know why no one else was purchasing them... THEY GROW LIKE WEEDS !!! And worst of all, I can't seem to get anyone to take the excess. Now that being said, I have been thinning out the "Crop" about ever 3 to 4 weeks by removing about half of the stalks. The "Crop" is not getting any smaller even with the thinning. I've come to terms with these little tan dancers and don't mind them in the tank, and actually have come to enjoy watching them. Now for the issue. About 2 weeks ago, I noticed that some of the Xenia had what I refer to as a "rash", the base of the stalk looks fine but moving up, as you approach the branches, there is an area of pitting and blistering of the flesh. They, are mainly symmetrical in appearance and vary in size from very small to .25" in diameter. This is the case on about 90% of the Xenia in the Tank, young and old. The Xenia are in small colonies spread from one end of the tank to the other; so I doubt that this is a case of physical aggression from another Coral body. If you disagree I will send a list of them, just don't want to bother you with an even longer message. I'm concerned because I have read that Xenia do not like, to the extent of fatality, high levels of Calcium. I recently achieved calcium levels of 475 by increasing the frequency at which I add my 2 part B-ionic solution. I now add it every couple of days.<Hmm, could be the calcium... or some matter that has/is becoming rate-limited by the pulsing corals abundant growth... or possible predation of some sort... but I would not be overly concerned... A die-off is not likely imminent> Question 2: I've recently seen two snail like critter in the tank. The first one was small and I removed. The second, have not removed and is about .75" long identical from the bottom (outside of glass) as the Astrea snails in color and physical appearance (head, foot, antenna). But, it doesn't have a SHELL !! instead it totes around what reminds me of a Medieval shield starting just above the head and ending about 1/2 way down it's back. As I'm sure you can tell the heart of my question would be: what is it and is it "bad" for the tank ? <Likely not... I would enjoy it, and other life until they prove to be deleterious... the vast majority of such "recruits" are innocuous> Here are the stat's checked monthly; these have been stable for 4 months now, save Calcium: SpecGr = 1.024 pH = 8.4 Alk = 3.43 Ammonia = <.25 <Really? as in zero?> Nitrate = 2.5 Calcium = 480ppm I'll not bother you with the list of Corals and such, since this spans the entirety of the tank. Fish: 3 Green Chromis 2 Kupang Damsels 1 Yellow Tang 1 Cirrhilabrus rubripinnis (Dwarf Parrot Wrasse) I think 1 Cleaner Shrimp 1 Clark's Clown fish w/ Anemone 1 Bicolor Blenny As always, Thank you in advance. John John Boiger <You're certainly welcome. Bob Fenner>
(Not) Sick Xenia Dear Bob, I was surfing the internet looking for discussions on xenia diseases and came across your name. Since your book "Conscientious Marine Aquarist" was the one that kicked off my two year marine aquarium adventure (well, mania!), I thought that I should say hello and thanks! Also, how about a bit of advice... <Salutem dicit. Hello there> I bought a colony of pulsing xenia about a year ago. The colony grows and is expanding. Since it often splits and the partners move away from each other, the colony is not crowded. Every so often, the pulsing heads shrink, often fall off (disappear) and I am left with a fat stem and no heads. However, in a week or two, new heads reappear and I have normal looking colonies. This event starts with one colony and migrates to others-but not 100% of the time. I have digital pictures of the effected colonies if it would help identify the malady. No issues with the rest of the tank inhabitants. I am fairly religious about following your maintenance routine. Any thoughts? Dan Pilipauskas <Yes, not really a malady, but more of a combination "reflex defensive mechanism" for coping with periodic "poor conditions" (lack of "food", current, toxicity...) and device for distribution in space and time. In another way, this is nothing to be really worried about, happens in the wild... Bob Fenner>
Xenia I just added a pulsing xenia to my tank, but it is not pulsing. I have a 100 watt metal halide and two 55 watt PCs. It is a 40 gallon tank. I have the xenia in medium-heavy current. What should I do? <Perhaps nothing, maybe a few things. I would move the animal out of direct "medium-heavy current" as this is more likely a problem than useful. I might look into aspects of my water quality (calcium, alkalinity, phosphate, nitrate) and adjust them environmentally if way out of whack. Many pulsing corals respond positively to iodine supplementation. Do you use such? Lastly, have patience. If you have "just added" the specimen, it may well be in "transport shock". Give it a few days to get situated. Bob Fenner>