For a lot of us SPS coral owners, there are a lot for us to worry: pests, parameter swings, phosphates, nitrates, RTN, and especially STN. With this many things to worry, why then go through the trouble of keeping these ‘fuzzy stix’? Well, the gratification that you get from years of nurture and growth is an indescribable. ONly those who have experienced this SPS euphoria could attest to its worth. So it is not easy when things go wrong. Especially when your well cared-for SPS corals start to STN (Slow Tissue Necrosis). It is really hard to feel helpless, as with STN, it is a common theme.
So what is it? How do we get it? How do we stop it? How do we prevent it from happening again? These are all questions that need to be answered for us to be able to attack this problem rationally.
Throughout my years of SPS nurture, I have witnessed many accounts of STN that do result in some positive and much negative outcomes. There are those instances where things improve without notice, and sometimes, never even give a coral a chance to survive. The coral’s ’skin’ recession begins at the base, and ends with the axial corallites (tips). So what is it really that makes the coral recede without warning? For now, the reasons are still ambiguous as there are many factors to consider. Some people claim that they see it begin with alkalinity swings. Some say that with temperature swings, you can get the same results. Currently, there is a new belief that in a low nutrient system (such as a Zeo, Ultralith), you can trigger an STN event. On that more later in part 2.
Here are some pictures of corals experiencing STN. Please note, these pictures are not for those of faint hearts:
- picture courtesy of zachslow from ReefCentral.com
- picture courtesy of sminker from ReefCentral.com
- picture courtesy of plancton from ReefCentral.com
- picture courtesy of reefrf from ReefCentral.com
- picture courtesy of reefrf from ReefCentral.com
- picture courtesy of sminker from ReefCentral.com
While many accounts of STN can be attributed to rapid temperature fluctuations, or even alkalinity swings, none can be more perplexing as some witnessed in an ULN System (Ultra-Low Nutrient System). Stay tuned in tomorrow for my explanation on why ULN Systems are not good for your reef and what you can do to combat it.
Related posts:
- STN and The Real Issues, part 3
- STN and The Real Issues, part 2
- Will The Real Superman Monti, Please Stand Up?
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I totally agree with you… I don’t like ULN system…
I have no idea what ULN is but doesn’t sound very healthy.. every living creature needs nutrients!
Conix, ULS is a reef system where you limit the available nutrients. Most people have to supplement their corals with Amino Acids, or ‘Coral Food’ to reestablish these nutrients.
Hi Vlad, I think that you have to supplement with Amino Acids and coral food in every way, but I don’t like to use bacteria to lower the nutrients, and to put your tank in a very complex world and so dangerous for your corals…
As far as I have been told, Amino Acids are a form of a protein, derived from things like fish food. So as long as you feed the tank, the breakdown of fish food (excess) will be just as good as adding amino acids on their own.
But I’m not so sure about this… what you say, I think, it’s correct, but I’m not so sure you can offer to your corals every type of amino acids they need through your fishes. In any case it is a very interesting point to discuss, I think we need to hear some biologists speaking about.
Thanks
Danilo
Amino acids (AA) are the building blocks of proteins – all proteins are made up of strings of AAs.
Now, in gdietary terms, there are two types of AAs – essential and non-essential. Essential means that you cannot synthesize these AAs and must consume (eat them) to have a supply of them. non-essential AAs, your body is capable of producing it’s own from more basic components from digestion.
The idea of feeding AAs to your ULNS is to replace what’s been stripped out by virtue of making it an ULNS. Many report seeing better growth with more feeding of their fish – the breakdown products (fish feces) and excess food probably provide all the AAs (nom/essential) the corals require.
I think ULNS is a funny, really unnatural wasteful system (beyond reefkeeping on it’s own). These people are using a lot of extra equipment and chemical additives since they’re over stripping their systems – why not just remove enough to get the desired results?
Thanks for the clarification. I knew that I was missing something from my oranic chem classes. The non and essential aminos.
Nice, my acropora is in the list! (third pic). Well, it was STN and the acropora got better, it was the only affected acro. The cause? I fragged a coral and used seachem´s coral dip (iodine), then I dipped the water with coral dip back to the tank as I thought the iodine would do it some good, however it seems to be some kind of unsuitable iodine and that caused the problem to that acro.
The STN stopped really quick, and then the acro regrew on the dead tissue.
Thats great to hear! Good that you have a stable system for the acropora to recover so easily. Many dont have that luxury, and lose a lot.
I think I like to see more SPS related topics on fragd.it
You ask, you get