Help with 240 Gallon System

[Nathaniellund17]

Hello All,
I'm looking for help with health on my 240 gallon system. It's been running for 2 and a half years, and I can't seem to have success with my SPS coral (and now appears one of my torches is dying.) I'm attaching some pictures of some SPS coral that appear to be dying. I think my water parameters and flow are fine - which leaves me with my lighting. Would welcome thoughts.

Here are the details on the system:
Display 180 gallon
4 Ecotech XR 30s for light
4 EcoTech MP 40s for flow

Sump 60 gallon
Protein Skimmer
Algae Scrubber
UV Sterilizer

I do weekly maintenance on the system, and am getting great growth from the algae scrubber that I harvest once per week.

First problem I think I could be having is with water quality. But from all the tests I've performed over time - it appears my water quality is where it should be. As to my water changes, I'm using Tropic Marin salt, doing a 30 gallon water change bi-weekly - along with dosing a BRS 3 part solution throughout the week.
As to water parameters, they are as follows:
Kh - Ranges from 8.5 - 9.0 (Hanna Checker)
Ca - 440 (Salifert Test)
Mg - 1,305 (Salifert Test)
NO3 - Ranges from 10 - 17 (Hanna Checker)
PO4 - Ranges from .03-.07 (Hanna Checker)

I've also done ICP tests, and everything was looking fine with some trace elements being a little low - though I pulled the water right before I performed a water change, so I'm thinking trace elements are okay as long as I perform water changes.

Second item I would consider is water flow. With the 4 MP40s, I have them running at 75%, and appears to be fine.

Third item is lighting. A few months back I rented a PAR meter, and brought the lighting from 40% capacity to 55% capacity which brought the PAR to 220-260 on my top layer of rocks. Bottom layer was 150-200. I've read that you need the high PAR for the SPS on top, and even though the lower level LPS don't need a high PAR, being with the high PAR would not necessarily hurt them - though I'm questioning that now with my Torch that's dying off. With the SPS now bleaching / dying off, I'm thinking my PAR is two high, as they were not bleaching / dying before I increased the capacity - they just weren't growing.

I'm kind of at a loss now, not knowing what needs to be done to help my coral. Would welcome everyones thoughts - if there's more detail needed, let me know.

 

[blaxsun]

You have enough lighting (in theory). Most of the SPS in my tank that's flourishing is in the 250-350+ PAR range.

 

[Stevorino]

How were the corals doing before the light increase? Were you increasing light because they were struggling already, or were they doing fine and you just wanted to up it to dial in the PAR to 'optimal'?

15% increase with four XR30s over a 180g tank is a pretty big jump, almost 40% increase relative to what it was previously.

I'm a pretty big believer that as you get into those higher par levels, the corals become more sensitive. That could be total nonsense, but at least in my experience, whenever I have pushed up the PAR to the levels you have cited below, it generally has not ended as well as I had hoped.

 

[Timfish]

Are you Dissolved OrganicCarbon (DOC) aka carbon dosing? And have you always run an algae scrubber? If so the DOCs from algae or from carbon dosing may be your culprit.

 

[Nathaniellund17]

How were the corals doing before the light increase? Were you increasing light because they were struggling already, or were they doing fine and you just wanted to up it to dial in the PAR to 'optimal'?

15% increase with four XR30s over a 180g tank is a pretty big jump, almost 40% increase relative to what it was previously.

I'm a pretty big believer that as you get into those higher par levels, the corals become more sensitive. That could be total nonsense, but at least in my experience, whenever I have pushed up the PAR to the levels you have cited below, it generally has not ended as well as I had hoped.

The Stilo was fine, but the others were not growing at all after months of being in the tank. When you state pushed up the PAR levels - are you meaning going to the mid-200s? Or just the % increase?

 

[Nathaniellund17]

Are you Dissolved OrganicCarbon (DOC) aka carbon dosing? And have you always run an algae scrubber? If so the DOCs from algae or from carbon dosing may be your culprit.

I am not carbon dosing. I have always run the algae scrubber. So you're thinking the DOC coming from the algae growing in the algae scrubber is causing the problem to the coral? Do you know of ways to test and rectify the problem?

 

[Timfish]

I am not carbon dosing. I have always run the algae scrubber. So you're thinking the DOC coming from the algae growing in the algae scrubber is causing the problem to the coral? Do you know of ways to test and rectify the problem

It's certainly a possibility based on a ton of research that been done. Unfortunately we can't test for DOC or more specifically the Dissolved Combined Neutral Sugars (DCNS) that can have a wide range of negative affects on corals. An Ebook (Ch 9) that was published by Burger's Zoo but has now been removed discussed the survival rate of coral in a big aquarium in Austrailia that used an ATS had a survival rate of just months for corals. If it was my system that would be the first thing I would do is remove your ATS and do larger than usual water changes for a few weeks or month to reduce the levels of DCNS that may have built up in your system. Don't bother trying to skim more or run more GAC as neither will work for DCNS. And keep your eye on alkalinity and PO4 so neither drop too low.

Here's a data bomb if you're interested in reading more on how algae has negative effects on corals.

"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

Microbial view of Coral Decline

Nitrogen cycling in hte coral holobiont

BActeria and Sponges

Maintenance of Coral Reef Health (refferences at the end)

Algae as Reservoirs for Coral Pathogens

Algae as Reservoirs for Coral Pathogens

Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens...

journals.plos.org

Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages.

Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages - PubMed

Increasing algal cover on tropical reefs worldwide may be maintained through feedbacks whereby algae outcompete coral by altering microbial activity. We hypothesized that algae and coral release compositionally distinct exudates that differentially alter bacterioplankton growth and community...

www.ncbi.nlm.nih.gov

Sugar enrichment provides evidence for a role of nitrogen fixation in coral bleaching

Error - Cookies Turned Off

onlinelibrary.wiley.com

Elevated ammonium delays the impairment of the coral-dinoflagellate symbiosis during labile carbon pollution
(here's an argument for maintaining heavy fish loads if you're carbon dosing)

Elevated ammonium delays the impairment of the coral-dinoflagellate symbiosis during labile carbon pollution

Labile dissolved organic carbon (DOC) is a major pollutant in coastal marine environments affected by anthropogenic impacts, and may significantly con…

www.sciencedirect.com

Excess labile carbon promotes the expression of virulence factors in coral reef bacterioplankton

Excess labile carbon promotes the expression of virulence factors in coral reef bacterioplankton - The ISME Journal

Coastal pollution and algal cover are increasing on many coral reefs, resulting in higher dissolved organic carbon (DOC) concentrations. High DOC concentrations strongly affect microbial activity in reef waters and select for copiotrophic, often potentially virulent microbial populations. High...

www.nature.com

Indirect effects of algae on coral: algae‐mediated, microbe‐induced coral mortality

Error - Cookies Turned Off

onlinelibrary.wiley.com

Influence of coral and algal exudates on microbially mediated reef metabolism.
Coral DOC improves oxygen (autotrophy), algae DOC reduces oxygen (heterotrophy).

Influence of coral and algal exudates on microbially mediated reef metabolism

Benthic primary producers in tropical reef ecosystems can alter biogeochemical cycling and microbial processes in the surrounding seawater. In order to quantify these influences, we measured rates of photosynthesis, respiration, and dissolved organic carbon (DOC) exudate release by the dominant...

peerj.com

Role of elevated organic carbon levels and microbial activity in coral mortality

http://www.int-res.com/articles/meps2006/314/m314p119.pdf

Effects of Coral Reef Benthic Primary Producers on Dissolved Organic Carbon and Microbial Activity
Algae releases significantly more DOC into the water than coral.

Effects of Coral Reef Benthic Primary Producers on Dissolved Organic Carbon and Microbial Activity

Benthic primary producers in marine ecosystems may significantly alter biogeochemical cycling and microbial processes in their surrounding environment. To examine these interactions, we studied dissolved organic matter release by dominant benthic taxa and subsequent microbial remineralization in...

journals.plos.org

Pathologies and mortality rates caused by organic carbon and nutrient stressors in three Caribbean coral species.
DOC caused coral death but not high nitrates, phosphates or ammonium.

http://www.int-res.com/articles/meps2005/294/m294p173.pdf

Visualization of oxygen distribution patterns caused by coral and algae

Visualization of oxygen distribution patterns caused by coral and algae

Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were...

peerj.com

Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates
Exposure to exudates derived from turf algae stimulated higher oxygen drawdown by the coral-associated bacteria.

Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates

Algae-derived dissolved organic matter has been hypothesized to induce mortality of reef building corals. One proposed killing mechanism is a zone of hypoxia created by rapidly growing microbes. To investigate this hypothesis, biological oxygen demand ...

www.ncbi.nlm.nih.gov

Microbial ecology: Algae feed a shift on coral reefs

Microbial ecology: Algae feed a shift on coral reefs - Nature Microbiology

Human pressures on coral reefs are giving macroalgae a competitive advantage over reef-building corals. These algae support larger, and potentially pathogenic, microbial populations that are metabolically primed for less-efficient, yet faster, carbohydrate remineralization, perpetuating a...

www.nature.com

Unseen players shape benthic competition on coral reefs.

Unseen players shape benthic competition on coral reefs - PubMed

Recent work has shown that hydrophilic and hydrophobic organic matter (OM) from algae disrupts the function of the coral holobiont and promotes the invasion of opportunistic pathogens, leading to coral morbidity and mortality. Here we refer to these dynamics as the (3)DAM [dissolved organic...

www.ncbi.nlm.nih.gov

 

[Nathaniellund17]

It's certainly a possibility based on a ton of research that been done. Unfortunately we can't test for DOC or more specifically the Dissolved Combined Neutral Sugars (DCNS) that can have a wide range of negative affects on corals. An Ebook (Ch 9) that was published by Burger's Zoo but has now been removed discussed the survival rate of coral in a big aquarium in Austrailia that used an ATS had a survival rate of just months for corals. If it was my system that would be the first thing I would do is remove your ATS and do larger than usual water changes for a few weeks or month to reduce the levels of DCNS that may have built up in your system. Don't bother trying to skim more or run more GAC as neither will work for DCNS. And keep your eye on alkalinity and PO4 so neither drop too low.

Here's a data bomb if you're interested in reading more on how algae has negative effects on corals.

"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

Microbial view of Coral Decline

Nitrogen cycling in hte coral holobiont

BActeria and Sponges

Maintenance of Coral Reef Health (refferences at the end)

Algae as Reservoirs for Coral Pathogens

Algae as Reservoirs for Coral Pathogens

Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens...

journals.plos.org

Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages.

Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages - PubMed

Increasing algal cover on tropical reefs worldwide may be maintained through feedbacks whereby algae outcompete coral by altering microbial activity. We hypothesized that algae and coral release compositionally distinct exudates that differentially alter bacterioplankton growth and community...

www.ncbi.nlm.nih.gov

Sugar enrichment provides evidence for a role of nitrogen fixation in coral bleaching

Error - Cookies Turned Off

onlinelibrary.wiley.com

Elevated ammonium delays the impairment of the coral-dinoflagellate symbiosis during labile carbon pollution
(here's an argument for maintaining heavy fish loads if you're carbon dosing)

Elevated ammonium delays the impairment of the coral-dinoflagellate symbiosis during labile carbon pollution

Labile dissolved organic carbon (DOC) is a major pollutant in coastal marine environments affected by anthropogenic impacts, and may significantly con…

www.sciencedirect.com

Excess labile carbon promotes the expression of virulence factors in coral reef bacterioplankton

Excess labile carbon promotes the expression of virulence factors in coral reef bacterioplankton - The ISME Journal

Coastal pollution and algal cover are increasing on many coral reefs, resulting in higher dissolved organic carbon (DOC) concentrations. High DOC concentrations strongly affect microbial activity in reef waters and select for copiotrophic, often potentially virulent microbial populations. High...

www.nature.com

Indirect effects of algae on coral: algae‐mediated, microbe‐induced coral mortality

Error - Cookies Turned Off

onlinelibrary.wiley.com

Influence of coral and algal exudates on microbially mediated reef metabolism.
Coral DOC improves oxygen (autotrophy), algae DOC reduces oxygen (heterotrophy).

Influence of coral and algal exudates on microbially mediated reef metabolism

Benthic primary producers in tropical reef ecosystems can alter biogeochemical cycling and microbial processes in the surrounding seawater. In order to quantify these influences, we measured rates of photosynthesis, respiration, and dissolved organic carbon (DOC) exudate release by the dominant...

peerj.com

Role of elevated organic carbon levels and microbial activity in coral mortality

http://www.int-res.com/articles/meps2006/314/m314p119.pdf

Effects of Coral Reef Benthic Primary Producers on Dissolved Organic Carbon and Microbial Activity
Algae releases significantly more DOC into the water than coral.

Effects of Coral Reef Benthic Primary Producers on Dissolved Organic Carbon and Microbial Activity

Benthic primary producers in marine ecosystems may significantly alter biogeochemical cycling and microbial processes in their surrounding environment. To examine these interactions, we studied dissolved organic matter release by dominant benthic taxa and subsequent microbial remineralization in...

journals.plos.org

Pathologies and mortality rates caused by organic carbon and nutrient stressors in three Caribbean coral species.
DOC caused coral death but not high nitrates, phosphates or ammonium.

http://www.int-res.com/articles/meps2005/294/m294p173.pdf

Visualization of oxygen distribution patterns caused by coral and algae

Visualization of oxygen distribution patterns caused by coral and algae

Planar optodes were used to visualize oxygen distribution patterns associated with a coral reef associated green algae (Chaetomorpha sp.) and a hermatypic coral (Favia sp.) separately, as standalone organisms, and placed in close proximity mimicking coral-algal interactions. Oxygen patterns were...

peerj.com

Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates
Exposure to exudates derived from turf algae stimulated higher oxygen drawdown by the coral-associated bacteria.

Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates

Algae-derived dissolved organic matter has been hypothesized to induce mortality of reef building corals. One proposed killing mechanism is a zone of hypoxia created by rapidly growing microbes. To investigate this hypothesis, biological oxygen demand ...

www.ncbi.nlm.nih.gov

Microbial ecology: Algae feed a shift on coral reefs

Microbial ecology: Algae feed a shift on coral reefs - Nature Microbiology

Human pressures on coral reefs are giving macroalgae a competitive advantage over reef-building corals. These algae support larger, and potentially pathogenic, microbial populations that are metabolically primed for less-efficient, yet faster, carbohydrate remineralization, perpetuating a...

www.nature.com

Unseen players shape benthic competition on coral reefs.

Unseen players shape benthic competition on coral reefs - PubMed

Recent work has shown that hydrophilic and hydrophobic organic matter (OM) from algae disrupts the function of the coral holobiont and promotes the invasion of opportunistic pathogens, leading to coral morbidity and mortality. Here we refer to these dynamics as the (3)DAM [dissolved organic...

www.ncbi.nlm.nih.gov

Thanks for the detail here. I still have to get through all the post. But to summarize, the ATS could be causing the problem. I’m thinking I’ll shut it down for a few weeks, monitoring closely. I am concerned about spikes in phosphates and nitrates… will just need to be ready for water changes as necessary.

 

[Timfish]

Thanks for the detail here. I still have to get through all the post. . .

Definitely read Rohwer's book first. He and his coauthor were able to present a very complex subject in a very readable format. One of the points they make that I'll reiterate here and explains some of the contradictions I've seen over the decades is thier discussion of an ecosystems equilibrim (pg 92 - 94). Somethng I've seen that didn't fit what the "gurus" claiming is corals doing better with an increase in nutrients as nuisance algae dissappeared. An ecosystem can have multiple stable states which promote different subsets of the biology of the ecosystem. Right now it seems the equilibrium of your system is antagoistic to corals and shifting the equilibrium will be more complex than just dealing with the nutrients we can test for. How long it will take is an open question not easily answered as we can't test microbiomes easily but I've seen systems take one to six months to correct themselves.

I've taken over a decade to find those links so and am still finding more as research into microbiomes and reef ecosystems expand. So don't feel like you have to know it all in the next few weeks ROhwer's book and video are the two most important IMO, everything else mostly just helps support the antagonistic roles of corals and algae.