Help Needed: Peeling and STN in Acropora Frags and Mini Colonies

[Kruss7]

Hi everyone,

I'm experiencing some issues with my Acropora frags and mini colonies, and I'm hoping to get some advice. Some of my SPS corals are showing signs of peeling and STN (Skeletal Tissue Necrosis), and it's quite concerning. Most of my acros look absolutely amazing but this seems like it’s going from one to another. This isn’t happening fast, the corals survive for days and I’m only loosing a 1-2 a week. They seem to hang on better after I dip them but eventually die anyways.

Parameters:
Temperature: 77.5-78.5°F
Salinity: 1.026 (35 ppm)
Alkalinity: 8.4 dKH
Calcium: 470 ppm
Magnesium: 1410 ppm
Phosphate: 0.08 ppm
Nitrate: 20 ppm

About a month ago, I experienced an alkalinity swing. It wasn't fast or super significant; it slowly dropped to around 6.5 dKH over a week and then gradually increased back to 8.5 dKH the following week. I'm not sure if this could be the cause, but it's a possibility. I'm am also currently waiting on ICP results, which should be available soon.

Interestingly, some of the SPS corals that have died were peeling with their polyps still extended. The peeling is strange as it isn't starting from the bottom up; spots on the branches are peeling first. I've dipped them and haven't found any pests, and there are no bite marks or eggs present. I had AEFW a long time ago, but haven't seen any since then and this isn’t looking like that did.

Could this be a bacterial infection? Any insights or suggestions would be greatly appreciated. I'm at a loss and want to save my remaining corals.

Thanks in advance for your help!

 

[Lavey29]

Age of the tank? A 2dkh swing could certainly cause SPS stress.

 

[Kruss7]

Age of the tank? A 2dkh swing could certainly cause SPS stress.

The tank is about 8 months old, most of the media, rock and sand is about 3 years old.

Would it be causing stress randomly jumping around weekly a month later? When I’m fragging off stuff that’s stning the frag survives about 50% of the time as well.

 

[Dburr1014]

Hi everyone,

I'm experiencing some issues with my Acropora frags and mini colonies, and I'm hoping to get some advice. Some of my SPS corals are showing signs of peeling and STN (Skeletal Tissue Necrosis), and it's quite concerning. Most of my acros look absolutely amazing but this seems like it’s going from one to another. This isn’t happening fast, the corals survive for days and I’m only loosing a 1-2 a week. They seem to hang on better after I dip them but eventually die anyways.

Parameters:
Temperature: 77.5-78.5°F
Salinity: 1.026 (35 ppm)
Alkalinity: 8.4 dKH
Calcium: 470 ppm
Magnesium: 1410 ppm
Phosphate: 0.08 ppm
Nitrate: 20 ppm

About a month ago, I experienced an alkalinity swing. It wasn't fast or super significant; it slowly dropped to around 6.5 dKH over a week and then gradually increased back to 8.5 dKH the following week.

Sadly, this is happened in my system more times than I care to admit. I have not experienced any losses because of it. I have raised my alkalinity one dkh per day for 3 days in a row to bring it back up.
I truly don't believe the alkalinity swing would cause peeling flesh on acros.

I'm not sure if this could be the cause, but it's a possibility. I'm am also currently waiting on ICP results, which should be available soon.

Interestingly, some of the SPS corals that have died were peeling with their polyps still extended. The peeling is strange as it isn't starting from the bottom up; spots on the branches are peeling first. I've dipped them and haven't found any pests, and there are no bite marks or eggs present. I had AEFW a long time ago, but haven't seen any since then and this isn’t looking like that did.

Could this be a bacterial infection? Any insights or suggestions would be greatly appreciated. I'm at a loss and want to save my remaining corals.

To me this does sound it could be a bacterial infection.

How is your overall flow in the system? Is it possible you can post a full tank shot in par numbers?

I'm not seeing a whole lot in your numbers that stand out, the only issue I see and people probably would disagree with me is the nutrient numbers. I would have liked to see less nitrates with your phosphate number.

 

[Kruss7]

Sadly, this is happened in my system more times than I care to admit. I have not experienced any losses because of it. I have raised my alkalinity one dkh per day for 3 days in a row to bring it back up.
I truly don't believe the alkalinity swing would cause peeling flesh on acros.

To me this does sound it could be a bacterial infection.

How is your overall flow in the system? Is it possible you can post a full tank shot in par numbers?

I'm not seeing a whole lot in your numbers that stand out, the only issue I see and people probably would disagree with me is the nutrient numbers. I would have liked to see less nitrates with your phosphate number.

That’s what I thought with the Alk swing, it was really slow and I’ve had far worse swings over the years.

I definitely suspect it could be a possible bacterial infection.

My tank is 220G peninsula, the flow is 3 MP60s running on high and 4 MP40s running on medium (both are reef crest) as well as 2 Vectra returns. I’m not really concerned with the flow.

I don’t have a picture with the par numbers but the tank has exactly the same par throughout it, I’m running 4 orphek v4 G2 Atlantic, 4 36” OR3 bars and 5 30” Blue Chinese LED bars. When I checked last Par at the top of my scape is between 500-600, middle is 300-400, bottom 200-300 and the sand is about 150-200. Nothing has changed in the lighting since being setup.

Currently working on lowering the phosphate and nitrate now slowly.

 

[Dburr1014]

That’s what I thought with the Alk swing, it was really slow and I’ve had far worse swings over the years.

I definitely suspect it could be a possible bacterial infection.

My tank is 220G peninsula, the flow is 3 MP60s running on high and 4 MP40s running on medium (both are reef crest) as well as 2 Vectra returns. I’m not really concerned with the flow.

I don’t have a picture with the par numbers but the tank has exactly the same par throughout it, I’m running 4 orphek v4 G2 Atlantic, 4 36” OR3 bars and 5 30” Blue Chinese LED bars. When I checked last Par at the top of my scape is between 500-600, middle is 300-400, bottom 200-300 and the sand is about 150-200. Nothing has changed in the lighting since being setup.

Currently working on lowering the phosphate and nitrate now slowly.

Just to be clear, I like your phosphate number, that's where I'd want to run.

 

[Kruss7]

Just to be clear, I like your phosphate number, that's where I'd want to run.

Okay, hoping I can get this to stop somehow.

 

[Lavey29]

The tank is about 8 months old, most of the media, rock and sand is about 3 years old.

Would it be causing stress randomly jumping around weekly a month later? When I’m fragging off stuff that’s stning the frag survives about 50% of the time as well.

8 month tank is still a young biome even with pre existing rock. Difficult to sustain SPS at 8 months. Very experienced reefers can do it but most of us lose stuff. The alk swing coupled with the young biome is causing STN on those frags. Cutting the good portion off may help some but I doubt it stops it for good. I lost SPS frags in the 8 to 10 month range but after a year the tank became much more stable and predictable and really haven't lost an SPS coral since.

 

[Dburr1014]

My tank is 7 months old then.
My rock cam from a 10 yo system except a 1/3 of it was dry.

Should they be dead?

There's this whole culture that says 1 year of dry rock before sps but if you buy real live rock from the ocean you're good to go.
If it doesn't fit those credentials, let's move the goal posts. 1 year for all rock before sps.

But some of us don't fit that logic. I moved everything in May after dipping all of my rock in ivermectin. I lost a clam recently and my biscuit star. My coral banded shrimp was 7 years old so can't count that. The biscuit stars don't do well in captivity. The clam I believe was exposure to the meds.
Haven't lost a coral. They are all growing.
I'm not tooting my horn, just saying this is a new setup and doesn't fit the logic.


OP, forgot to tell you, is dim the lights some. Probably 20% will help let them rest some.

 

[SeaDweller]

STN is SLOW tissue necrosis, not skeletal tissue necrosis.

My current tank is only about 2 months old, but with rock from a ten year old system. I basically broke it down, tank sat empty for a week and then rock went back in and about a month later all acros (frags, colonies, etc) went in. I agree, experience helps, so how new to keeping sps are you?

Point being, your system is not really different than mine age wise, in that sense, so I’d look at yourself or something else causing your problems, and eliminate the age thing from the equation.

 

[Lavey29]

My tank is 7 months old then.
My rock cam from a 10 yo system except a 1/3 of it was dry.

Should they be dead?

There's this whole culture that says 1 year of dry rock before sps but if you buy real live rock from the ocean you're good to go.
If it doesn't fit those credentials, let's move the goal posts. 1 year for all rock before sps.

But some of us don't fit that logic. I moved everything in May after dipping all of my rock in ivermectin. I lost a clam recently and my biscuit star. My coral banded shrimp was 7 years old so can't count that. The biscuit stars don't do well in captivity. The clam I believe was exposure to the meds.
Haven't lost a coral. They are all growing.
I'm not tooting my horn, just saying this is a new setup and doesn't fit the logic.


OP, forgot to tell you, is dim the lights some. Probably 20% will help let them rest some.

Each tank is unique and the experience skill level of the reefer plays a critical role too. I can see coralline in your tank which is a good indicator of tank health and puts you ahead of the curve compared to most at 7 months. Could OP problems be bacterial ? Sure they could. Could it be lack of tank maturity with the biome for SPS? Sure it could. We see both scenarios commonly here in threads.

 

[Kruss7]

STN is SLOW tissue necrosis, not skeletal tissue necrosis.

My current tank is only about 2 months old, but with rock from a ten year old system. I basically broke it down, tank sat empty for a week and then rock went back in and about a month later all acros (frags, colonies, etc) went in. I agree, experience helps, so how new to keeping sps are you?

Point being, your system is not really different than mine age wise, in that sense, so I’d look at yourself or something else causing your problems, and eliminate the age thing from the equation.

I’ve kept SPS for 4 years. Like I said most of my acros are extremely happy this isn’t a system wide thing. Just so confusing seeing corals rapidly growing and colours like below and then some STNing beside them with their polyps out and coloured up.

 

[Kruss7]

Each tank is unique and the experience skill level of the reefer plays a critical role too. I can see coralline in your tank which is a good indicator of tank health and puts you ahead of the curve compared to most at 7 months. Could OP problems be bacterial ? Sure they could. Could it be lack of tank maturity with the biome for SPS? Sure it could. We see both scenarios commonly here in threads.

It’s too bad it’s so difficult to figure out. Like I said and you can see in the pictures most of my sps is thriving. Still waiting on the ICP, who knows maybe it’ll reveal high metals or something. Might actually check to make sure there is no stray voltage as well.

 

[Dburr1014]

I’ve kept SPS for 4 years. Like I said most of my acros are extremely happy this isn’t a system wide thing. Just so confusing seeing corals rapidly growing and colours like below and then some STNing beside them with their polyps out and coloured up.

These all look like frags.
Do you have colonies?
Are colonies suffering as well?

Full tank shot with white lights on?

 

[Kruss7]

These all look like frags.
Do you have colonies?
Are colonies suffering as well?

Full tank shot with white lights on?

I have mostly frags left. 2 of my 3 colonies I had I have lost. I have one left that isn’t doing so hot. The frags that I have are from my previous tank and are a lot smaller as cutting them off the rock proved to be difficult. The larger mini colonies or colonies actually seem to be more likely to stn. Not home but will get a full tank shot soon.

 

[Lavey29]

I would Kung fu dip those struggling frags

 

[Dburr1014]

I have mostly frags left. 2 of my 3 colonies I had I have lost. I have one left that isn’t doing so hot. The frags that I have are from my previous tank and are a lot smaller as cutting them off the rock proved to be difficult. The larger mini colonies or colonies actually seem to be more likely to stn. Not home but will get a full tank shot soon.

Hmmmm, colonies are struggling, frags are good.
Are the colonies tight?

And you are sure flow is good.
It's random, high flow?

 

[bobnicaragua]

This is tough, your acros look happy and I don’t have a problem with any of your numbers. If the small PH swing is to blame, you should be past that really soon.

Are you considering treating with cipro? It might be worth a shot.

Over the years, the more things I do to increase PH, the happier my acros tend to be.

 

[klc]

I had the same issues with frags, ends up I found a few corals with AEFW egg clusters. But you stated you've found none of that so let's hope it's something else

 

[wrassie86]

Could these issues coincide with cold rolling in and house being sealed up? I live in Maine and I've noticed over the years that if my tank is going to suffer a bit, it is from NOV to FEB roughly and generally only acro.