Table Recession

[Dr B]

Anthony and others...
Over the past few days i have noticed some recession, and i have noticed it spreading on my table.

Obviously this type of recession is due to a lack of something. I am not sure if it is lack of flow, light, or what. The recession seems to be in a lower flow part, and pretty well shaded. Take a look at the pics (the last two are w/ flash and note the recession... green part)

So what do you propse I do. I have tried to move one of my outputs to get more flow there in the meantime... but it is really giving that coral quite a bit of velocity in the flow. Going to see if it likes it or not...
Should i puddy/superglue over the recession spot? Cut it off?
I dont know if this type of recession will spread even to healthy areas of the coral, or just stick to the unhappy areas of the coral.

I had some recession like this on one of my large samoensis colonies at the base. Once I moved it over to my new tank the coral started encrusting back over the area it had died. I dont know why it liked the new tank better than the old, but something stopped the slow recession and it began to heal.
thanks for the thoughts guys

 

[Ed Hahn]

Dr B,
Do you have any soft corals in your tank? I am often reminded that softies stunt the growth of SPS at times. I would assume the new growth is more sensitive than the mature area of coral. That is just a guess, but something is affecting its growth. Softies such as Kenya trees, Toad stools leathers, etc... Maybe I am just preaching a old tune I am often reminded of. I could use another lesson Dr B.
Good Luck,
Ed

 

[Dr B]

No softies in the tank.... nothing near the spot of recession.
thx

 

[mattj206]

Looks like shade poisoning...

Has the coral been there long?

Has the part in shade for long?

I have some corals that do this when base is shaded, and others that can power past the shade ? On shared energy ?

 

[Dr B]

its been there for 4 or 5 months.

 

[Anthony Calfo]

very good point, Ed. Danke

For the benefit of other readers/archiving, the presence of unnatural amounts/species of soft corals in garden reef tanks is quite a challenge to husbandry. Its especially difficult after events of propagation or stress to the animal. Octocorals often are very noxious.

Dr B... as you suspect, there are many possible reasons for "bleaching" and an address of the issue is quite a yeoman's chore starting with a definition of "bleaching" (arghhh... what a can of worms!).

With a general symptom, not much tank history (husbandry, hardware and livestock inventory, etc)... there is little for us to speculate upon.

What we can speak to is some of the common catalysts for you to consider.

One of the most under-rated in my opinion is a lack of adequate food/nutrition. Some corals will carry for months/years and even grow... but over time, a net daily deficit in nutrition can and will catch up to us. Imagine, if you will, that you have perfect lighting, whatever that means. Most popular corals that we keep are only sustained by the products of photosynthesis in the 70-85% range. The best we can hope for is just over 90%... in fact, I'm not sure that anyone can definitively say which if any coral is wholly zooxanthellate-autotrophic. Hmmm... in laymans terms, practically no coral that we keep/can name can be fully sustained by photsynthesis without supplemental feeding by absorption and/or organismal/filter-feeding. And our lighting really is far from perfect as you may suspect, without using natural sunlight.

Thus... with Acroporids that may be getting, say, 80-90% of their daily demand (source of carbon/nitrogen) from the products of photosynthesis... that still leaves 10-20% of their daily demand needing to come from somewhere other than light! Adding more light cannot satisfy this demand as the coral approaches/passes the saturation point(the point at which no more light can produce more food, so to speak via zooxanthellae). Worse still if we push corals with excess light to the point of photoinhabition (zooxanthellae shut down/light shock). Interestingly, though... deficiencies in lighting CAN be compensated for with extra food/feeding.

The bottom line is that corals need fed And that most corals are not adequately fed in aquaria. And even if you satisfy 99% of their daily needs via light and food... that still means the coral is living on a net daily deficit of 1% and will slowly starve to death in time. The situation is generally much worse than 1% in captive corals, however, and may explain many of the apparent deaths by symptoms of "consumption" (tissue recession without evidence of necrotic infection, disease, etc) after some months or even years of seeming to fare well.

As to what to feed sps... that is a tricky question. It varies by species... a wild range of accepted particle sizes... even prey shapes/types. And few if any prepared foods can adequately satisfy this demand. I am in strong favor of very large fishless, coral-less refugiums (mature over one year) as means of supplying nutritive matter to corals. Some folks like DSBs to support this... and there may very well be some prepared foods of use/utility (have heard mention of a new zooplankton product coming on the market soon comprised of very small and nutritious mollusk larvae/eggs collected - interesting!)

As to other possible causes for this corals ailment... inadequate water flow perhaps, aged lamps, sudden increases in water clarity (tardy use of carbon/ozone, abrupt change of lamps), etc.

Still... your pics don't look like "bleaching" from light shock to me... as best as I/one could tell from a photo.

Another fear I have for you here is a pathogen. And that reminds me that most aquarists do not properly quarantine all new livestock without exception (snails, algae, corals, fishes, LR, LS... everything!). And so... all bets are off regarding pathogen, parasites, pests and diseases when one plays the russian roulette game of adding anything wet (new livestock) to an aquarium without 4 week QT.

Some food for thought

kindly,

Anthony

 

[Ed Hahn]

Anthony,
Would DT's Phytoplankton possibly help Dr B?
Love this thread..
Thanks in Advance
Ed

 

[Dr B]

Thanks for the info anthony.

Here is the tank history in this thread .
I am also blend my own food up in bite sized chunks for my fish, which also makes lots of little particles that hopefully the corals are feeding on.(made-up of snapper, scallop, shrimp, and some other goodies for the fish)

I always think of bleaching as shock from light, and since this area is green I wasnt sure what it is. What I am concerned about is if it is going to keep spreading, and if it is something that I can combat by getting rid of the bad tissue. I have had great luck with RTN... any time ive had it i have saved the coral. In fact I had a piece that i sawed through about 7'' of a entire coral base and saved the whole colony.
So didnt know if this was some sort of disease or a deficiency. Is there anything I can do to help in your synopsis?
Thanks

Oh and as far as husbandry thats not updated on my link...
I run carbon every few weeks, I do weekly 5-10% water changes, and I am using 25micron filter socks 24/7 now.
The bulbs were changed out several weeks ago, and I have a par meter so I have been acclimating them appropriately(atleast with intensity)

 

[Dr B]

Acros do not utilize phyto directly. The zooplankton eat phyto and the coral eats the zooplankton.

On my old 120g with a DSB i cultured my own rotifers, brine shrimp, and 3 kinds of phytoplankton. Way to much work... I have done away with the DSB yet i have a awsome pod population in my rock(and on my glass i might add).
Instead of providing zooplankton now directly, when i blend up my fish food, i get different sized particles that should be feeding my sps also.
All of my other sps in the tank are doing great(and theres a lot of em).

 

[DonW]

I'm having the same problem, only with acros. Digitata's all look great. Ive been wondering for a while if the filter sock may be stripping all the food. Also I'm getting zero growth from acro and very little on everything else except coraline which is growing like crazy.

Don

 

[Angelscrx]

Anthony you are goooooooood!!!!!!!!!!!!!!

Great info man.

 

[Dr B]

Don,
All of your acros, a specific piece, or a specific type?
This is the only weird spot i have noticed on my acros since this tank. In my other tank I had this problem with a samoensis like i said, but now in this tank it encrusted over that spot and is doing great.

 

[Anthony Calfo]

I think the best course of action here (with concerns for the rest of the tank's inhabitants - mostly the other Acroporids) is to remove the specimen to a proper isolation tank. I do not make such recommendations casually while reckoning the stress/inconvenience of moving such animals into qt for 4+ weeks and then back again. But I do think it will be best here to serve the greater good.

In QT (and display tanks) where nitrates are "zero"/undetectable, I often recommend the addition of a nitrate solution (to 5-10 ppm) as a source of food for zooxanthellate corals. You can do this easily with a solution of sodium nitrate (yes... fertilizer). Some of the Europeans do this in old, mature tanks with massive stony coral growth where even huge loads of fishes do not provide adequate supplies of nitrogen for the coral colonies.

If your nitrate levels are near zero.. do consider this as a quick and easy support.

If the recession is progressing slowly, I would not frag or epoxy this animal just yet.

Anthony

 

[DonW]

Don,
All of your acros, a specific piece, or a specific type?
This is the only weird spot i have noticed on my acros since this tank. In my other tank I had this problem with a samoensis like i said, but now in this tank it encrusted over that spot and is doing great.

Dr B,
I only have three or four different small acros, but yes all of them have reacted the same. The first week they look fine, then no polyp extension and then bleaching. The Digitata's and Montipora's all have great polype extension but are dull in color and very little if any growth. I have a digitata frag thet has been in the tank for 4 moths and has not even began to encrust.
Anthony brings up a very good point or something else to try anyway's. My Nitrates have always been 0 (undetectable) since the day the tank cycled.

Anthony,
To bring Nitrates up what exactly should we use and how?
My fish population is (90 gallon):
1 sailfin (medium)
1 perc. clown
1 psuedochromis (small)
1 grn chromis (small)
1 Lawnmower (large)
1 Anthias (medium)
Although I would like to add a fish or two I'm unsure as to whether or not my population is to high or not. I do run the felt filter sock 24/7 so my skimmer really is not working hard at all.

Thanks for the help
Don

 

[big t]

Well, I can honestly say that I have never heard anyone recommend adding nitrates to help with sps coral growth. I have always heard that excess nutrients will just feed the brown zooanthelle and make the corals turn brown.

 

[DonW]

Well, I can honestly say that I have never heard anyone recommend adding nitrates to help with sps coral growth. I have always heard that excess nutrients will just feed the brown zooanthelle and make the corals turn brown.

I've heard they need to be stable at 8-10 for corals. But honestly never understood why and never did anything about it.

Don

 

[big t]

If you have nitrates of 8 to 10 there will be some serious algea problems. Everything that I have ever read says that a undetectable nitrate reading is very desirable for a sps system, and necessary for good coloration.

 

[DonW]

If you have nitrates of 8 to 10 there will be some serious algea problems. Everything that I have ever read says that a undetectable nitrate reading is very desirable for a sps system, and necessary for good coloration.

My guess is to add some nitrates in order for it to be broken down into nitrogen gas, which would be good for the corals. I dont think the idea is to add large quantities of nutrient high in P. P is what will build up and cause the corals to turn brown and stop growing.

Just a guess
I'm sure Anthony will get back to us on this one.
Don

 

[Dr B]

Im with you Big T....

 

[Anthony Calfo]

ooh, I should be specific here too. When I say/suggest 5-10 ppm nitrate, I mean the actual nitrate (ion) concentration... not merely the reading as nitrate-nitrogen that you get from hobby test kits (which you must multiply by 4.4). So 10ppm on most hobby test kits is actually 44 ppm (too high indeed and algae-ville in many systems)

That said, there is not much information in English hobby literature regarding supplemental nitrate solutions. I've gotten word of it mostly from annual trips to Europe. There is a brief mention of it though in Daniel Knops "Giant Clam" book. Its not rocket science though... just a little bit of (healthy!) fertilzer that can make a difference in nutrient poor tanks or tanks that oterwise cannot produce adequate nutrition for corals like Acroporids. For such species that are so small polyped and so discriminating (particle and prey size/type)... do consider what (anything?) they are eating in your aquarium? If your nitrates are zero... and no bottled supplement can deliver much or enough/any adequate substitutes for prey (bacteria, floc, nanoplankton)... then they are not eating much if anything at all, no?

It may not be the principal cause in this case... but it is a common problem overall for aquarists.

As to how much to use to get to a 5-10ppm actual range of nitrate... more than a few ways to do this. But the short and sweet answer is to make a stock solution (as we do with iodine, strontium, etc):

mix one gram of sodium nitrate with 1000 ml of water to make a dilute stock solution.

try dosing 10 ml of the stock solution per 100 liters (~26 gall) to push the envelope and approach your targeted nitrate concentration in the system.

And much like iodine or feeding, if dosed slowly and in small amounts over time, you will notice a slight increase in nuisance algae perhaps... then you can simply back down to a slightly lower dose/level and carry on.

But above all.. simply obey a good and accurate test kit to meter your nitrates in support.

Anthony