Help, please, with relentless STN

[BeanAnimal]

Have you considered vibrio as a possibility? And if so, using a product like PNS Probio as a means to displace bad bacteria with beneficial bacteria?

Can you explain how we would identify and selectively replace the role of any specific bacteria? It is an honest question. Even if we knew the exact bacterial strain attacking the SPS, what remedy would target that strain while distinguishing it from beneficial bacteria, even if we could define beneficial bacteria?

Taken to the extreme, we could use an antibiotic, but what we cannot account for are the short or long term side effects. Even narrow-spectrum antibiotics are broad in this context.

But let’s back up. STN and RTN are not diseases; they are symptoms. Despite the research, no single cause or pathogen has been identified for coral tissue necrosis. The general understanding is that some stressor causes an overall drop in the coral’s immune response. At that point, it becomes a general opportunistic issue where any number of normally benign bacteria may take advantage of compromised tissue.

I am not saying Vibrio, or any other bacterial type, isn't or can't be involved. I am saying we can't know if it is the cause or just being blamed after the fact. So where does adding “beneficial bacteria” to displace “bad bacteria” fit in, especially when neither can be defined, let alone blamed.

I do not see an overt issue with using PNS Probio, but I would stop there, short of making any specific claim about what it may do or help.

I hope that makes sense.

 

[CHSUB]

What about adding some "good bacteria"

Maybe, it is not something I would consider or do, mainly because I have never done it. I agree with what you’re attempting as there is no easy answer, do to impart that your aquarium looks very nice.
GL

 

[BeanAnimal]

What about adding some "good bacteria". A few people on the thread have also suggested trying to shift the bacterial balance away from the pathogenic state I'm in at the moment to a more balanced one.

That all sounds fancy and is repeated often, but contextually, what is pathogenic here? See above. We do not know what causes STN, but we do know it is not a single type or class of bacteria, even if certain bacteria are present in some cases. Think of STN as a syndrome, not a disease. Even though it may spread in a system, we cannot identify exactly what is spreading or why.

Think of the environment as the pathogen, and instead of invaders, think of opportunists. We also do not know what fixes it. Water quality is always a start. We can hand-wring about abstractions like “pathogens” and “microbiome balance,” but the problem is that we have no actionable data.

Mike Paletta swears he solved his dogged STN issues with Cipro. Others have not had the same success. We just do not know.

 

[BeanAnimal]

Let me digress here for a moment and point out what we do know.

• We do not know what causes it.
• STN and RTN are not diseases. They describe tissue loss, but no single causative organism has been shown to satisfy Koch’s postulates.
• It can appear to spread, but that does not mean it is spreading from coral to coral. Rather, corals may be reacting to some stressor in the same manner. That may be why, in some systems, it only affects certain types of corals, while in other systems the spread may be broader or appear random.
• Often, intervention does not directly fix the issue, but coincidence makes it appear that it has.

Something as simple as a very upset coral releasing aggressive chemical warfare may be the cause. In other cases, it very well could be a specific fungus or bacteria creating the stressor. In other cases, it could be as simple as a water quality swing and base parameters that set up the failure.

This all makes it a very hard problem to solve, and trial and error is about the best we can do. Water quality is a reasonable start. As Bear indicated, maybe adding bacteria will help, maybe not. Maybe moving to a different set of baseline water parameters will help, and maybe moving corals or changing lighting will help. There are just so many variables that it is all a guess, and none of it is really educated by more than hobby lore.

 

[Reginald Reefer III]

PNS bacteria is good stuff

 

[carri10]

That all sounds fancy and is repeated often, but contextually, what is pathogenic here? See above. We do not know what causes STN, but we do know it is not a single type or class of bacteria, even if certain bacteria are present in some cases. Think of STN as a syndrome, not a disease. Even though it may spread in a system, we cannot identify exactly what is spreading or why.

Think of the environment as the pathogen, and instead of invaders, think of opportunists. We also do not know what fixes it. Water quality is always a start. We can hand-wring about abstractions like “pathogens” and “microbiome balance,” but the problem is that we have no actionable data.

Mike Paletta swears he solved his dogged STN issues with Cipro. Others have not had the same success. We just do not know.

Hiya. Glad you have chimed in.
What you state above frustrates me more than anything in this hobby. I see all sorts of questions here on "are we focusing too much on chemistry", "do we have the right biome" etc etc. And the debates nearly always come down to "we just don't know". As a scientist, i struggle to live with that, but it is absolutley true.

But, your post has reminded me that we are dealing with complex systems and so we should be using systems thinking to try to solve. Your framing of S/RTN as symptoms and environment as pathogen helps.

What are the levers i can control in this system - inputs - food, water quality, lights, chemistry, mechanical filtration...
As always, get these solid and then see where we are. This dovetails nicely with CHSUB advice.

I think I'll start here (although my parameters over the last 2 months have been solid) and see where I get to.
Fix the base, remove anything that is not specifically needed (EasyReefs Pro) and then build from there.
Only problem, so many parameters and when does patience need to face up to a coral loss every two weeks...

 

[carri10]

Maybe, it is not something I would consider or do, mainly because I have never done it. I agree with what you’re attempting as there is no easy answer, do to impart that your aquarium looks very nice.
GL

:-) Did look very nice!. Does not currently.
I'll keep pushing on.

Bright side - I get to go coral shopping again once I have stabilty with the remaining ones for a few months - save up for a Christmas present.

 

[BeanAnimal]

Hiya. Glad you have chimed in.
What you state above frustrates me more than anything in this hobby. I see all sorts of questions here on "are we focusing too much on chemistry", "do we have the right biome" etc etc. And the debates nearly always come down to "we just don't know". As a scientist, i struggle to live with that, but it is absolutley true.

But, your post has reminded me that we are dealing with complex systems and so we should be using systems thinking to try to solve. Your framing of S/RTN as symptoms and environment as pathogen helps.

Yes the recent trend of decorating everything with abstract scientific terminology to arrive that the same "we don't know" is frustrating. But worse, the repetition here, YT, etc. is weaving misinformation into the body of the collective knowledge and turning into "reef science".

I can't take credit for that framing, that is what the people who do the science say! I am just repeating what I have researched.

What are the levers i can control in this system - inputs - food, water quality, lights, chemistry, mechanical filtration...
As always, get these solid and then see where we are. This dovetails nicely with CHSUB advice.

That is a fine perspective from where I sit.

Only problem, so many parameters and when does patience need to face up to a coral loss every two weeks...

It is one of the hardest problems in SPS to solve. I wish I had better answers and I don't.

 

[vetteguy53081]

Hi all.
I have been suffering from STN for about two months now and I can it see what is causing the problem. The thing that confuses me the most is i have deaths from Acros, Millies, alveolora, galaxia, stylophora, pocillapora, and euphyillia.

Here is a general photo of my tank before this began. You can see the tank (just 2 years old) is doing alright.

Here are some photos of today.

I have a ICP, attached, where things seem okay ( not perfect, but okay) and this chemistry has been stable for months and months. I understand that the Molybdenum and barium are high, but according to the report, they are well within acceptable, if not optimal, conditions.



Nitrate hovers between 15 and 20, phosphate is 0.3 (I have another thread on that.), again both constant for months and months.
In terms of what I’ve changed, I did remove all mechanical filtration and move to a cryptic sump with sponges et cetera at the beginning of the year. That led to a general reduction in redox, but no effect on the corals that I could see.

Water changes are 1.4% a day. Nyos salt. Dosing is with food grade or higher reagents in a home-made dosing recipe following Randy‘s advice. This has not changed for months and months.
I include my pH and alkalinity traces, along with salinity and temperature.

I did have some troubles controlling temperature until I bought a chiller about a month ago but the temperature never went above about 26 celcius or so and even then only for a day. I can’t see why that would’ve led to this unstoppable STN.

You can see the traces here;
Redox

Alk

Temp (celcius)

Salinity (ppt). Note,. some of this variation is due to probe drift, some is real. I'd put it at about 50:50 probe, vs actual drift.

PH

Can anyone help me out here, as every week I am losing another animal with no real idea how to stop it.

Thanks for any advice, even the most basic.

Sorry to see. Some possible triggers of infection are often a change in salinity, temperature and salt mixes. Additionally, Elevated phosphate, light and even new light and elevated alkalinity levels will be a higher risk to coral. Other minor factors will be low Dissolved oxygen, new corals especially leathers (which emit a toxin known as Terpenes), false test kit readings and newly added rock can alter chemistry.

 

[carri10]

Sorry to see. Some possible triggers of infection are often a change in salinity, temperature and salt mixes. Additionally, Elevated phosphate, light and even new light and elevated alkalinity levels will be a higher risk to coral. Other minor factors will be low Dissolved oxygen, new corals especially leathers (which emit a toxin known as Terpenes), false test kit readings and newly added rock can alter chemistry.

Thanks for the input.



A few things, from the initial tone of your reply, I read a kinda of defeatist air (starting with the simple "sorry to hear that"). Should I prepare myself for the worst case here (loss of maybe half my corals or more), or does this burn itself out usually?



Next, you've mentioned a lot of triggers there, but I feel that RTN/STN is waiting to happen when a reef is close to the edge of it's safe operating window, and then one of those triggers tips it over the edge. Question is why is it close to the edge?


I had been swayed at the end of last year, by the idea of running a more natural reef, with less mechanical filtration and a large cryptic area for sponge growth to help the filtration and supposedly (after reading a lot on this site) helping a positive sponge /coral cycle.

I removed my filter roller and reconfigured the sump. I have a reasonable exciting cryptic sump, although by no means explosive sponge growth, so I assume my particulate load is higher, due to no mechanical filtration and no sponge explosion from them eating it all up. Could it be that I have pushed my balance towards too much organic matter (particulates that can degrade to soluble organics) and this has moved my reef to the edge of its safe window? A salinity change that wouldn’t normally cause a problem now sets off a negative spiral of STN.

All of this is unprovable, but searching for cause and effect, the greatest change is the removal of mechanical filtration and the cryptic sump. Last year I had the same types of salinity/alk changes, but not RTN.

Maybe this is the problem? Just sort of thinking out loud here…

 

[CHSUB]

Just sort of thinking out loud here

I’m doing the same with my response….

I had been swayed at the end of last year, by the idea of running a more natural reef, with less mechanical filtration and a large cryptic area for sponge growth to help the filtration and supposedly (after reading a lot on this site) helping a positive sponge /coral cycle

I think the idea of running a more natural reef is an excellent direction. It is my preferred approach and I have seen fantastic results that includes mangroves and sensitive spa corals.



I’m not sure if removing mechanical filters gets you closer to a more “natural” approach? Imo, natural would include inorganic nutrients far below hobby testing detection and frequent inputs of organic nutrients. I don’t think removal of mechanical filters gets you closer to this goal?

 

[DCR]

Any reason for running 10-11 alkalinity? That seems excessive to me for SPS. I would slowly dial that back to at least 8-9 or even lower.

 

[fish_collector]

STN/RTN is a hard one to figure out.

 

[13rodo]

I had been swayed at the end of last year, by the idea of running a more natural reef, with less mechanical filtration and a large cryptic area for sponge growth to help the filtration and supposedly (after reading a lot on this site) helping a positive sponge /coral cycle.

I removed my filter roller and reconfigured the sump. I have a reasonable exciting cryptic sump, although by no means explosive sponge growth, so I assume my particulate load is higher, due to no mechanical filtration and no sponge explosion from them eating it all up. Could it be that I have pushed my balance towards too much organic matter (particulates that can degrade to soluble organics) and this has moved my reef to the edge of its safe window? A salinity change that wouldn’t normally cause a problem now sets off a negative spiral of STN.

All of this is unprovable, but searching for cause and effect, the greatest change is the removal of mechanical filtration and the cryptic sump. Last year I had the same types of salinity/alk changes, but not RTN.

Maybe this is the problem? Just sort of thinking out loud here…

TL;DR If it were me, I'd revert back to the original filtration and see if that starts to help. Then once you are stable you can come up with a plan to swap back to the filtration you'd like.

As I've become an older, more salty engineer (software) I find myself reverting more and more to K.I.S.S. (Keep It Simple Stupid) when teaching young engineers. Systems get very complex very quickly. As smart as we all think we are, the human brain's ability to keep track of effects from multiple and often branching chains of reactions isn't really that great.

I often run into this scenario:
Young Engineer: Hey this was working, but now it isn't.

​

Me: List all the changes that took place between working and now.​

​

Young Engineer: Well I did this #1, this #2, and that, but those don't impact the thing that is breaking.​

​

Me: Well obviously it did. Revert back to your known good point, instrument the code, run your data. Add this #1 back, run. Does it still work? Compare instrumentation data and analyze how that impacts downstream systems. Add this #2 back. Does it still work? Compare instrumentation data and analyze how that impacts downstream systems. How does adding this #2 impact the instrumentation data versus adding only this #1. Keep adding things back until the confounding effect reveals itself.​

​

Young Engineer: That's a lot of work.​

​

Me: Welcome to debugging! If you can teach yourself to be disciplined and methodical with it, you can fix anything.​

You've identified what changed. I'm not smart enough to know how that could impact corals, but it's pretty reasonable to assume that the biggest upset to this complex system is the stressor. If you have some data pre-change and post-change that'd probably give you a pretty solid understanding of what your previous filtration was doing that your current is not.

 

[carri10]

It’s a good way of looking at it, although I can’t go back to a filter roller. I can put an external canister in place, instead.

The swings in parameters so far this year are not unique and happened over the last 2 years now and then. However, they never had anything like the consequences I am living with.
So something has changed and the filter is the obvious thing.
@CHSUB advices on general nutrients chimes well with this. It’s also true that PO4 was never a problem until recently. I put that down to rock saturation.

Anyhow. I’ve upped the filtration with a quick filter /powerhead combo. I’ve stopped all easyreefs feeding and I’m moving to a monthly 50% sandbed clean to try and reduce overall organics. Non-nutrient Parameters have been rock solid now for nearly 2 months. So let’s Hope this works.
I’m also going to dose in Special Blend and TheraP from microbe-lift.

Do know what the worst is? When I fix it, I’m not going to know exactly why and will be unable to pinpoint anything that helps my, or the hobby’s, wider understanding.

By the way- how bad can this get? Can I lose all of my corals, LPS, SPS and softies? Do you know?
The tank was looking so good beginning if this year…

 

[WildOne]

I got a pdf from a link somewhere on the forum, I think Jay Heimdal had posted the link? Handbook coral pathology: identification and management in aquaria, by oceano monaco institut oceanographique. That may turn out helpful, and its free.