FAQs on Stinging-Celled Animal Behaviour Related Articles: Cnidarians, Water Flow, How Much is Enough, Related FAQs: Anemone Behavior, Stony Coral Behavior, Zoanthid Behavior, Soft Coral Behavior, Xeniid Behavior, Cnidarians 1, Cnidarians 2, Cnidarian Identification, Cnidarian Compatibility, Cnidarian Selection, Cnidarian Systems, Cnidarian Feeding, Cnidarian Disease, Cnidarian Reproduction, Acclimating Symbiotic Reef Invertebrates to Captive Lighting,

To Cover Or Not To Cover; That Is The Question -- 12/16/10
Hello to all with the crew,
<<Hiya Beth>>
Haven't written in a while what with one thing and the other but I've a few questions.
<<Okey-dokey>>
Question 1: I have been running Power Compacts (2 10,000 K daylights and 2 Actinics along with blue LED's) on my 125 gallon (6 foot) reef tank for years with no issues however, the colors of corals I can keep seem to be limited to green or tan and random purples.
<<Hmm'¦ You don't give the wattage, but even if these are 96w PCs, I expect this tank could use a bit more, regardless of the stockings'¦and in the 10,000K range versus Actinics>>
Any other colors I get brown out. Reading multiple articles has led me to wonder if this is related to the high nutrient levels I maintain (deliberately as this is a lagoon type set up), which would contribute to a higher Zooxanthellae population per coral
<<One of several factors to consider>>
or to the fact that I have a double barrier between the lighting and the tank (moisture protecting plastic strip below lights and a glass canopy on tank to reduce evaporation).
<<Another contributor>>
Since both barriers can reduce UV lighting,
<<Indeed'¦along with total output across the entire spectrum>>
and corals color up as a protection against UV light,
<<A factor, yes'¦but in of itself, not the 'whole story' re coral coloration>>
would it make sense to remove one or both of those barriers?
<<In my opinion'¦yes. Removal of the 'plastic strip' will increase light penetration. Removal of the 'glass canopy' will increase light penetration and arguably, gas exchange>>
Do you think this would increase the colors on for example, my Acans or Favia? (both a rather bland grey or tan with color only at the oral disc)
<<Can only help in my opinion, considering the type and intensity of your current lighting system. But as eluded earlier, lighting is not the sole answer to coral coloration. As you mentioned, nutrient control can be a factor'¦along with nutrition/feeding and the availability (lack of) of key amino acids. Water chemistry is also a player here. An imbalance/shortage of bio-minerals can also cause some corals to lose color/intensity, in my experience>>
Question 2: I have an elegance coral who appears to be doing quite well but I have questions related to its feeding. I currently feed a little bit of whatever I am feeding the fish. This could be Formula 1, Formula 2, Plankton, Marine Cuisine, etc.., quite varied and something different every day but not much of it. I thought that this would be a bit more along the lines of how they eat in their natural environment but noticed in your posts frequent suggestions for larger, meatier feedings twice a week or so.
<<This is mainly if the coral 'is not' getting what it needs from your daily feedings. If the coral is feeding and doing well now, I see no need to change your methodology>>
Since I do maintain a high organic load (no skimming and very little true filtration, just random water movement), and since it does appear to be doing fine, should I just continue my current practice?
<<Sure'¦for the reason just stated>>
I do 30% water changes every 3 weeks or so and am not concerned with over feeding so much. The elegance, along with the Wellsophyllia, Acans, anemones, and Favia, appear to eat everything I give them and never regurgitate so I thought I was doing ok.
<<If this is the case then yes, I would agree>>
Other possible contributing factors:
PH: 8.3 ish (varies from 8.1 to 8.3
Nitrate: 10-20 ppm
<<Some Nitrate is important to both health AND coloration. These levels are likely fine for the biotope/livestock you have, though striving to keep it toward the lower end of this range may prove best>>
Alk: 9 to 11 dKH (I do have to buffer every week or so).
Calcium: 400 avg.
Phosphate: 0 but using API and have had other forums state a not very accurate test kit
<<Might I suggest a Salifert or Seachem kit then. Or if you want to get really accurate, one from Merck or Hach>>
Temp: 78
SG: 1.024
<<I would raise this to NSW levels (1.025/1.026)>>
Thanks as always for your advice and work.
<<Happy to share>>
Sincerely,
Beth
<<Poor coral coloration is often a combination of factors in my experience. Try 'clearing the path' so to speak, for your lighting as discussed'¦and maybe lower those Nitrates just a bit (add a skimmer or some chemical filtration) and see what that does. Adding a couple more 10K PC bulbs would also help, in my opinion. You could also look in to some of the amino acid supplements available'¦and/or add some Selcon to your feeding regimen. Eric Russell>>

Re: Coral Growth 8/6/08 Sorry, I have the aforementioned tank with some Xenia, a Goniopora, some zoos, a Cabbage Leather coral and a Green Star polyp. What can I give these guys to get them to start growing faster? Right now I'm feeding Cyclop-Eeze and using Kent's Lugol's iodine at the rate of two drops per week. My Xenia are getting taller stalks, but not spreading or pulsing very well. I am also using B-Ionic for calcium and Alkalinity. What do you recommend for optimal growth? <There are many factors, including lighting and water flow, in addition to the feeding that will have an impact on your coral's growth and overall health. http://www.wetwebmedia.com/growingcorals.htm and linked articles/FAQ's will give you some insight to your questions above.> Thanks, Devin Haney <Welcome, Scott V.>  

Coral Lifespan 12/5/06 Hi, hope everyone is having a nice day <So far, so good.> One of my customers asked me about how long does <do> corals normally live? Some one told him they only live a few months and now he is kind off scared to invest in a reef tank. <A true statement... with poor care.> Could you maybe enlighten me on the average lifespan of LPS, SPS and soft corals in general? I know this is quite difficult as you do not know how they will be cared for, but an estimate if cared for properly, would surely help. <There is really no lifespan length for corals.  Corals are always reproducing under proper conditions.  If a polyp should die, new ones are always forming.  Example: I have a colony of Yellow Polyps, the original colony consisted of eight polyps.  There must be close to 200 polyps now.  What happened to the original eight, still alive, don't know, don't care, I have nearly 200 now.  Stony corals are much slower growing, but still reproduce under proper conditions.  Reefs are formed in the same way, stony corals growing on top of dead coral skeletons, soft corals smothering rock.  Again, keep in mind...under ideal conditions.  Read here and linked files above for information on growing/keeping live corals.  http://www.wetwebmedia.com/growingcorals.htm> Thank you <You're welcome.  James (Salty Dog)> Wikus

How do they move without muscles? Cnidarian beh.   8/23/06 Quick question crew. Just wondering, do anemones and corals have myosin/actin fibers? If not how do they move their extremities? -Mike <Do have muscles/fibers... see any Marine Invertebrate survey text. Bob Fenner>

Newly Placed Coral Drooping - 01/23/2006 I have a question regarding a new coral I placed in my tank. <Let's hear it!> I do not know the exact name of the coral as I could not find an exact picture anywhere. <Not even labeled at the place you purchased? Not a good start.> I can only describe it as a leather coral that appears to have several baby fingers sprouting like a tree with no polyps on it.  Anyway, when I purchased it, it was standing very tall and looked great. <Ok, that's more promising.> When I brought it home, floated it, and then placed it in my tank it looked fine for a while. <You mean you used a freshwater fish type acclimation, on a coral!? Really not a good start. These are sensitive to drastic environmental changes (temp., lighting, general param. swings).> A few hours later I came  back to look at it and found my conch sitting at the base of it. I pulled the conch off and moved him to a different part of the tank. Over time the coral has begun to droop. <The snail was moved not the coral, right? To be expected at this point.> This is in a 50 gallon tank with a pc light. The coral resides about 6 inches from the surface. <Hard to say if this is appropriate for the coral without knowing what it is.> Everything else in the tank looks great ( including other corals) and my tests come back within specs. <Ok, so you do have some coral experience. Whew! I'll have to take your word on the tests here.> Can you tell me if this is a temporary thing that should eventually come around or is this something to be concerned about? <Probably stress from the introduction. Don't touch (at all), and make sure it is getting what it needs (light, flow, foods if necessary). Should be able to correct for it self.> Thank you for your wonderful source of information! Sea8n <You're welcome. - Josh> Plerogyra on the skids, too lazy to read, news at 11:00 We have a sick bubble coral. He has totally deflated and has long brown stems coming out of his mouth. Can we help him? Is he dying? K <Uhh, try reading what is posted re stony coral health, the family Caryophylliidae... on WWM. Bob Fenner> 

Yellow polyp not opening Hey guys, <Cheers> It's 8:30 am in Montreal and the weather is cold. Sometimes I wonder why we all live here!!  <I have traveled places like that myself... Arizona in August... Boston in January... why, why, why are human beings habitating there. Moreover... how?!?!> Well... my question in straightforward, my yellow polyp which I bought two weeks ago is not opening up. I searched your site and could not pinpoint the problem.  <The first problem here is that we cannot know what coral specifically you are talking about (common names mean little). By yellow polyps do you mean Parazoanthus, Tubastrea, A Sarcophyton, etc.?> He was opened at the LFS under power compact light. All my parameters are within normal range, except calcium which is 260. <Do water changes to get your Calcium and Alkalinity more even keeled (probably high from mis-dosing supplements). Read here too, brah: http://www.wetwebmedia.com/calcalkmar.htm > I do have 175 MH lights. The polyp is placed midrange, with moderate to heavy flow and moderate lighting.  <I'm thinking/fearing, hearing a lack of QT for this new coral here. Sigh. It may explain light shock if any... or illness from infection or disease pending and possibly at risk of infecting your display, etc. You may learn a very hard lesson mate. I do hope not. Yet you need(!) to understand and apply strict quarantine habits for all new livestock if you will be a conscientious aquarist> I've been feeding him Marine Snow every second day and I just started feeding him Mysis shrimp. I went to my LFS and he said that usually these pacific type polyps like lower levels of light, so now he's at the bottom of the tank. Oh yeah, one other thing, he's not attached to any type of sponge but rather just live rock. Any thoughts, should I let it be or should I be worried? Nilesh <Do send a scientific name and/or pic for us to be clear here. Kindly, Anthony>