Millepora acros wither away while most other acros thrive.

[KGV]

I have a 220 gal tank with about 25 acropora species. Nearly all of these are thriving but in the last few months, I have seen several millepora corals slowly wither away. The curious thing is that it is only my millepora corals. The sequence of events is pretty stereotyped. They first show hints of green tissue (see attached example), then polyps retract (first at the base and finally on the tips), and then STN kicks in (also starting from the base and upwards).

I do 15% water changes with Red Sea blue bucket every week. PO4 is at 0.07, NO3 at around 1 ppm. There is good availability of these elements as I have lots of fish that get 1 gram of frozen mysis/krill and 1 gram of pellets per day and good algae growth on the glass. I don't add anything more except for two-part + kalk and I have a refugium with chaeto.

Lights may be on the lower side; LEDs , coral care gen 2 with 250-ish PAR, but I have a lot of flow by anyone's definition. Other elements I try to keep to natural salt water (for example KH 7.5-ish). I can list all params but there is nothing unusual about them, so not sure how useful that would be. I am just hoping that this stereotyped process of decline rings a bell.

Many thanks in advance!

 

[Camaro Show Corals]

Are you using a dosing pump or calcium reactor? Normally stn at the base is a sign of alk swinging. I will say in my experience millis do best in the highest of light and flow. Most of mine are in 500-600 par and most intense parts of flow. What are you using for flow?

 

[Timfish]

Consider you might have a species specific disease. Immune systems vary significantly at the genotype level and a specimen of a gneotype with a weak immune system can spread a disease to healthier specimens of stronger genotypes. Many corals are propogated with methods that may increase thier color or growth but can also cause weakened immune systems also. If you're carbon dosing stop as increased labile DOC is strongly associated with increased pathogens in coral microbiomes. What might be best is not do anything that will cause additional perterbations in the ecosystem and wiat a few months to see how it plays out. Here's some links if you're intersted:

Higher stress and immunity responses are associated with higher mortality in reef-building coral exposed to a bacterial challenge

Understanding the drivers of intraspecific variation in susceptibility is essential to manage increasingly frequent coral disease outbreaks. We challenged replicate fragments of eight Acropora millepora genotypes with Vibrio spp. to quantify variation in lesion development and to identify host...

www.biorxiv.org

Intraspecific differences in molecular stress responses and coral pathobiome contribute to mortality under bacterial challenge in Acropora millepora - Scientific Reports

Disease causes significant coral mortality worldwide; however, factors responsible for intraspecific variation in disease resistance remain unclear. We exposed fragments of eight Acropora millepora colonies (genotypes) to putatively pathogenic bacteria (Vibrio spp.). Genotypes varied from zero...

www.nature.com

"Coral Reefs in the Microbial Seas" This video compliments Rohwer's book of the same title (Paper back is ~$20, Kindle is ~$10), both deal with the conflicting roles of the different types of DOC in reef ecosystems. While there is overlap bewteen his book and the video both have information not covered by the other and together give a broader view of the complex relationships found in reef ecosystems


Changing Seas - Mysterious Microbes


Nitrogen cycling in hte coral holobiont


BActeria and Sponges


Maintenance of Coral Reef Health (refferences at the end)


Optical Feedback Loop in Colorful Coral Bleaching

 

[KGV]

Are you using a dosing pump or calcium reactor? Normally stn at the base is a sign of alk swinging. I will say in my experience millis do best in the highest of light and flow. Most of mine are in 500-600 par and most intense parts of flow. What are you using for flow?

I use a dosing pump. I think Alk is pretty stable. In the last half a year it has always been between 7.3 and 8.0. Flow: 2x Tunze 6585, 2x Red Sea Gyres 45, and 3 Nero 5's.

 

[LIreefguy]

Thank you these videos and links are very helpful
I been carbon dosing for years on my tank. Couldn’t figure out why I buy sps. Then do well for a little. One grew from a 1 inch frag to a 5 inch colony then died in a day
I know it could be other things. But didn’t even consider the carbon dosing. I have stopped carbon dosing last 3 months.

 

[Mr. Roboto]

I have a 220 gal tank with about 25 acropora species. Nearly all of these are thriving but in the last few months, I have seen several millepora corals slowly wither away. The curious thing is that it is only my millepora corals. The sequence of events is pretty stereotyped. They first show hints of green tissue (see attached example), then polyps retract (first at the base and finally on the tips), and then STN kicks in (also starting from the base and upwards).

I do 15% water changes with Red Sea blue bucket every week. PO4 is at 0.07, NO3 at around 1 ppm. There is good availability of these elements as I have lots of fish that get 1 gram of frozen mysis/krill and 1 gram of pellets per day and good algae growth on the glass. I don't add anything more except for two-part + kalk and I have a refugium with chaeto.

Lights may be on the lower side; LEDs , coral care gen 2 with 250-ish PAR, but I have a lot of flow by anyone's definition. Other elements I try to keep to natural salt water (for example KH 7.5-ish). I can list all params but there is nothing unusual about them, so not sure how useful that would be. I am just hoping that this stereotyped process of decline rings a bell.

Many thanks in advance!

I am curious on the two part plus kalk, do you have a FTS? Any others besides the photos above?

 

[KGV]

I am curious on the two part plus kalk, do you have a FTS? Any others besides the photos above?

What is an FTS?

 

[Mr. Roboto]

What is an FTS?

Front Tank Shot

 

[KGV]

I will post a few when I am back home.

 

[randalli]

For me it was similar. All Acros grew like crazy except for the Milles. Looked great at the start but couple weeks later the problems started. No polyp extension and then seemingly STN from the base. Tried everything because I was pretty sure that my flow is great. Nothing worked. Lastly I changed my flow pumps and am now blasting them with the most random and chaotic flow I can create. The ones that do best are like 10cm from an MP40 running at around 55%. My lighting is a T6 with 4 blue, 1 actinic, 1 2500k but my milles are not even closest to the light. They are like in the middle of the tank hight wise. But blasted full on. The only other things I do is feed 1/4 of the recommended Reef Energy Plus like 2-3x/week and keep my NO3/PO4 above 0. KZ Flatworm stop might help as well but but it might lower NO3/PO4 too.

 

[KGV]

Front Tank Shot

 

[KGV]

Here is an overview

 

[sculpin01]

In my opinion, this a bacterial process. One of my tanks has struggled with a similar issue. Everything grew great for awhile and then I started seeing slow tissue loss at the base and browning of growth tips. ICP negative for heavy metals or other contaminants. Per recommendations from a thread with a similar issue, I tried three days of ciprofloxacin which led to significant improvements in about 50% of corals (the target bacteria here being Arcobacter). I started with Florida live rock, so I suspect an SCTLD-like syndrome killing my nonresponder corals. Currently, I am almost done with 5 days of amoxicillin (drug of choice for SCTLD). I’ll try to update the results thereof. BTW, I’ve seen no ill effects of antibiotic treatment with exception of one fish that developed lateral line issues with ciprofloxacin.

 

[sfg]

I ran into a similar issue here recently.. all my millepora lost PE and started to get pale. No STN however. Then other types of acros started showing similar signs. ICP test looked great, except one thing which I totally overlooked, my salinity. Ive been using a Milwaukee digital refractometer for about 3 years now, and ashamed to say i never calibrated it since new. Well.. it was reading 35ppt but was 3ppts off. ICP showed 38ppt. I corrected this and things turned around within 3 months. Still have a few millepora colonies that are recovering but the high salinity was the cause for me anyway.