Algae release "useful proteins, carbohydrates and metabolites."

[Lasse]

From an article attached to my first post (my bold)

Findings revealed that organic matter released from both algae predominately
consisted of carbohydrates (59 ± 5%) and proteins (32 ± 7%), which mainly (89 to 93%)
dissolved in surrounding waters. Traces of fatty acids (C16:0; C18:0) and chl a were also found in
algae incubation waters, but in a quantitatively negligible amount. Carbohydrate analysis further
showed that glucose was the dominant glycosyl released by algae, accounting for 77 ± 8% of the
carbohydrate fraction and 42 ± 8% of TOC. Galactose (9 ± 4% of carbohydrate fraction), mannose (6 ±
3%), xylose (4 ± 1%), rhamnose (3 ± 1%) and fucose (2 ± 1%) were also detected in all incubation
water samples.

I can find articles that will fill at least 10 pages with quotes like this - but I do not think it’s necessary

No further comments

Sincerely Lasse

 

[Want2BS8ed]

I guess by this point, since Triton has not answered, that they do not intend to do so.

Randy, after 3-years have you not learned that you are supposed to "eat the hamburger" and not question where it came from or what is in it?

This is the point I should insert an LOL, but then again it is not very funny. Dodge, duck, weave... or just refuse to answer.

 

[Vaughn17]

I guess by this point, since Triton has not answered, that they do not intend to do so.

I would imagine not.

 

[Vaughn17]

"Organic carbon" may mean many things; macrolides (antibiotics) are "organic carbon", aminoglycosides (antibiotics) are also, and are sugars, both. The practicality of all organic products, including toxins, are "organic carbon", so referring to organic carbon does not apply much light to any discussion.

Unfortunately there are very few works specifically directed to our hobby, which entails more heat than light in the confrontation of opinions, but over time we will be able to develop somewhat more controlled experiments and we will be able to distinguish more easily what serves us or not.

Best Regards

"which entails more heat than light in the confrontation of opinions,"

You're a master wordsmith!

 

[gregkn73]

Why we see papers that indicates that algae releases toxins for corals, when so many reefers , use for many years macroalgae and ats to control nutrients, with great success and no adverse effect on corals, is something I can not understand. especially while by this topic , we wanted to learn more info, about the possibly possitive effect on corals, from the organics released by macroalgae...

 

[Chris86]

Guys, the only thing he wants to know is if there is a legitimate study that shows what Triton is saying is true. Usually such a study would be a controlled study. He’s a scientist, and scientist make a hypothesis and somehow test it. There is a lot of math. Statistics. It’s either proven to make a difference at a certain confidence interval or not.

Feel free to make as many hypothesis as you’d like, but I think he wants to see some literature supporting triton’s statement

 

[Broadwave]

Very interesting post and following along... but after 5 pages in on this thread, very surprised @Randy Holmes-Farley hasn't gotten a straight answer on what seems like legitimate question to the algae die off claims made my Triton.

 

[Jose Mayo]

Why we see papers that indicates that algae releases toxins for corals, when so many reefers , use for many years macroalgae and ats to control nutrients, with great success and no adverse effect on corals, is something I can not understand. especially while by this topic , we wanted to learn more info, about the possibly possitive effect on corals, from the organics released by macroalgae...

Until very few years, the articles on interaction of algae and corals in natural reefs were almost nonexistent. Special lines of credit, linked to studies of the consequences of global warming, derived from human activity (according to the hypothesis), have allowed the Universities of the world to look into these ecosystems and are now reaping the benefits.

The themes are complex, they are not specifically back to the interactions artificially produced in the world of aquarism and there is no real commitment to cause and effect, just the clue.

Many of the readings that are made, of sugars, just for example, are more quantified by the monomer, not by the identification of the polysaccharide. An example is glucose (monomer) versus cellulose and starch (polysaccharides whose monomer is glucose) ... the way these three forms of sugar behave in biology and the ecosystem is distinct, but they are often read as one thing by the chemical detection process.

At present, what we do have is the empirical results of the work of the pioneers, and thanks to them we have gained some victories in keeping our animals in captivity, even those formerly considered "impossible", but ... if any these results of the work of the Academy, at least serve to make us more attentive, will have already been worth the effort to look for them and study them at some lost hour of the day.

Best regards

 

[Scrubber_steve]

This thread started with a very reasonable question being asked by Randy Holmes Farley.
It was then taken off topic, by some, and morphed into an anti-algae filtration seminar, misusing scientific papers to advance misleading blanket statements.

I’d like to make some points on the second phase.

Healthy reefs have & need algae. They also have virulent bacteria, and all sorts of chemicals in the water column, exuded by all photosynthesising organisms, and others, that are potentially detrimental to other organisms. Everything has a place & purpose.

But, as made very clear, in every paper one reads on algae allelopathy and its detrimental effects on coral reefs, there are three common factors –

1. Only certain species of algae are responsible for coral decline.

2. Much of the problem is due to the algae growing directly among coral species, and also coming into physical contact with the coral.

3. It is only when these specific species of algae proliferate to a biomass significantly higher than what typically exists on a healthy reef, due to external forces, they become a problem.

External forces are responsible for algae biomass increase. Nutrient run off from land is one mechanism. Another is the reduction in population, and/or, diversity, of algae grazing fish and invertebrates as a result of over fishing, and/or disease.

eg. from Morrow. et al https://webcache.googleusercontent.com/search?q=cache:nBs8p5r2an4J:https://pdfs.semanticscholar.org/0d70/17f332aff334a3a08e865dd390c391f63f7e.pdf+&cd=1&hl=pt-BR&ct=clnk&gl=br

– “Macroalgae are major competitors with corals and other benthic organisms on tropical reefs, especially where rates of herbivory are low and nutrient enrichment is high” (Fong and Paul 2011; Rasher and Hay 2010).

eg. from Bhattacharyya. et al http://aimsciences.org/article/doi/10.3934/dcdsb.2017146 – “Macroalgal proliferation and coral diseases”, “The abundance of macroalgae changes the community structure” and “In coral reef ecosystems, macroalgae and corals compete intensively for the available space in seabed and the grazing by reef herbivores prevents algae to proliferate. In the absence of herbivory by reef fishes, the faster growing macroalgae often overgrow corals by causing their decline”
end


When the biomass of these species of algae increase, so does the volume of detrimental chemicals exuded into the water column. At some point these chemicals, directly and/or indirectly, begin to interfere, one way or another, in the healthy functioning of the coral holobiont.

In Morrow. et al, specific species of algae are noted as being detrimental –
two species of Dictyota brown algae -
Dictyota menstrualis: Thallus erect, 15-25 cm high. yellow brown to dark brown, dichotomously branched blades strapshaped, 2-15 mm wide
Lobophora variegate: medium to dark brown, drying dark brown to black, 4–10 (–14) cm long and as much across

3 species of red alga
Delisea pulchra: medium to dark red-brown, fading to yellow-grey, 10–35 cm high, much branched complanately from the margins
Asparagopsis armata: pink to red when fresh, drying grey-brown to dark red, 80-250mm tall, with long, feathery main branches covered with dense, irregular, radial, short tapering side tufts
&
Callophycus serratus.


In Bhattacharyya. et al –
Halimeda opuntia: Thick, profusely branched clumps of rounded three-lobed or ribbed leaf-like segments, between 10 and 25 cm in height. The branches are numerous and are in different planes, rather than nearly in a single plane as some other species are. This alga can cover larger areas with a dense mat so that individual plants are indistinguishable.
Also from Bhattacharyya. et al – “Proliferation of benthic macroalgae in coral reefs results in increased physical contacts between corals and macroalgae leading to an increase in exposure to pathogens.”

Morrow states - "A well-known function of macroalgal compounds is to provide chemical protection from abundant and diverse herbivores. Previous studies suggest that as herbivorous fishes and invertebrates selectively remove palatable species of macroalgae, they are replaced by unpalatable, chemically defended seaweeds. The results of this selective herbivory are commonly seen on many coral reefs that have undergone phase-shifts to increasing dominance by chemically defended seaweeds, including species of Halimeda, Dictyota, Lobophora, and cyano-bacteria of the genus Lyngbya. Members of these 3 chemically defended genera are now the most abundant macroalgae on many reefs in Florida and the Caribbean, reaching 7–17% cover at some sites" (K. M. Morrow pers. obs.).

So from that, I would assume that the particular species of ulva that grows naturally on my scrubber screen, that my fish eat, is a "palatable species of macroalgae" and there-fore safe to use as a filtering media, especially considering the small amount of it on the screen at any given time.


So to summerise; it is only certain species of algae that are a problem, only when they are able to proliferate, & mostly due to growing directly among coral, and when physically contacting coral.

Considering the Triton method of algae filtration; - Using multiple species of algae, in a large fuge, as recommended.
Should one be very careful when selecting the algae species to use in the fuge? Or should one, perhaps, just use the hobby friendly chaeto algae alone?

Should one just let the algae grow, and partially die off, continually, as recommended? Or would exporting it regularly, to prevent die off be better?

Should one consider using such a large amount of algae in a fuge, as recommended by Triton? Or would it be better to use a far smaller, but efficient amount of algae, as is typical in an algae scrubber, for example?

 

[Scrubber_steve]

This part speech by Julian Sprung at MACNA 2017 is very informative regarding algae allelopathy

at 41:53

 

[Jose Mayo]

Aprioristic conclusions in complex matters, although they may be sincere, are not always correct. "To be convinced" is not synonymous with possessing the truth, so what must be done is to continue the search, so that the truth appears ...

Still on the "good things" that algae release:

Microbial to reef scale interactions between the reef-building coral Montastraea annularis and benthic algae

Highlight: "... while lipid-soluble extracts (i.e. allelochemicals) from some algae have been shown to damage corals, these compounds are highly specific to the algal species and require direct contact for effect [36]. In contrast, DOC is a water-soluble product of photosynthesis that is potentially released by many algae [51,63] and does not require contact to affect the coral holobiont. Various forms of DOC released by algae have been shown to kill corals and increase microbial growth rates [40,41], while some algae cause coral death and hypoxia that is mediated by microbes [38]. Coral exposure to DOC also induces coral-associated viruses [64] and increases the proportion of pathogens on corals [39], and algae that release more DOC likely show a stronger effect [39].

The work is interesting because it refers extensively to the interaction of corals with turf algae, quite present in the hobby ... and in the ATS.

Best regards

 

[Scrubber_steve]

Microbial to reef scale interactions between the reef-building coral Montastraea annularis and benthic algae

Highlight: "... while lipid-soluble extracts (i.e. allelochemicals) from some algae have been shown to damage corals, these compounds are highly specific to the algal species and require direct contact for effect [36]. In contrast, DOC is a water-soluble product of photosynthesis that is potentially released by many algae [51,63] and does not require contact to affect the coral holobiont. Various forms of DOC released by algae have been shown to kill corals and increase microbial growth rates [40,41], while some algae cause coral death and hypoxia that is mediated by microbes [38]. Coral exposure to DOC also induces coral-associated viruses [64] and increases the proportion of pathogens on corals [39], and algae that release more DOC likely show a stronger effect [39].

The work is interesting because it refers extensively to the interaction of corals with turf algae, quite present in the hobby ... and in the ATS.

This is repetitive, and I’m not arguing against anything stated in any paper. Katie et al highlight nothing different to what is already stated in the other studies already mentioned.

The same types of fleshy algae’s – brown algae Dictyota bartayresiana, and Halimeda opuntia are highlighted. They state clearly that it is the proliferation of these algaes, due to external forces, that is the problem. And again, it’s shown that the more significant issue is with the close proximity of algae growing directly among the coral, & algae / coral physical contact, not algae in some remote corner several meters away.
I'll re-summerise, just incase you missed it the first time; it is only certain species of algae that are a problem, only when they are able to proliferate, & mostly due to growing directly among coral, and when physically contacting coral.

In regards to turf algaes, I don’t, & I don’t know of anyone else, who grows “turf algae” on a scrubber screen. Perhaps that’s what Walter Addey use to grow back in the olden days? I’m not sure. Turf algaes are typically described as multispecies assemblages of diminutive, mostly filamentous algae that attain a vertical height of only 1 mm to 2 cm. Often exist as assemblages (algal turfs), are ubiquitous in reef systems and are composed of the small, juvenile stages of macroalgae (e.g., Gelidium spp., Gelidiella spp., Digenia simplex) along with faster-growing filamentous species (usually red algae such as Polysiphonia spp., Herposiphonia spp., and Ceramium spp.; blue-green algae (cyanobacteria); diatoms; brown algae; green algae; and coralline algae) and detritus and sediments.


My ‘ATS’ grows two genus of emerald green Enteromorpha, but it’s difficult to know what specific ones exactly. They certainly aren’t ‘turf’ algaes, or fleshy, & they certainly aren’t spreading around, and all over my corals. There’s zero algae in the display, excluding coralline.

I don’t need to worry about allelopathy as the algae I grow is unlikely to be exuding these specific toxins, the amount of algae contained in a scrubber is miniscule, & activated carbon & water changes will negate the problem even if it exists.

 

[Lasse]

1. Only certain species of algae are responsible for coral decline.

2. Much of the problem is due to the algae growing directly among coral species, and also coming into physical contact with the coral.

3. It is only when these specific species of algae proliferate to a biomass significantly higher than what typically exists on a healthy reef, due to external forces, they become a problem.

Thank you

Sincerely Lasse

 

[gregkn73]

To gain something useful from this thread.....as I wrote, I AM sure from my experience but also from so many hobbyist's tanks around the world, that ATS and chaeto don't make any harm to the corals ,growing in our DT. I now know from Lasse paper reference, that they produce useful organics=carbohydrates and proteins. What I would like to know is, if those useful organics produced by algae, are in quantities, that can make any significant difference to my system? If there is any paper ,giving answer to that question, I will be very glad to know.

 

[Scrubber_steve]

To gain something useful from this thread.....as I wrote, I AM sure from my experience but also from so many hobbyist's tanks around the world, that ATS and chaeto don't make any harm to the corals ,growing in our DT. I now know from Lasse paper reference, that they produce useful organics=carbohydrates and proteins. What I would like to know is, if those useful organics produced by algae, are in quantities, that can make any significant difference to my system? If there is any paper ,giving answer to that question, I will be very glad to know.

Putting aside the various carbs algae exude, perhaps the variety of proteins- aminos & vitamins they exude are benificial?

 

[Lasse]

Putting aside the various carbs algae exude, perhaps the variety of proteins- aminos & vitamins they exude are benificial?

I´m in the same box of thinking - therefore I try to use my skimmer more as gas exchanger than a protein remover. I cant fix my gas exchange in an other way at this moment - therefore I still use a skimmer. i have my fuge before the skimmer - have it after - should it be a better choice (in this context)?

Sincerely Lasse

 

[Lasse]

To gain something useful from this thread.....as I wrote, I AM sure from my experience but also from so many hobbyist's tanks around the world, that ATS and chaeto don't make any harm to the corals ,growing in our DT. I now know from Lasse paper reference, that they produce useful organics=carbohydrates and proteins. What I would like to know is, if those useful organics produced by algae, are in quantities, that can make any significant difference to my system? If there is any paper ,giving answer to that question, I will be very glad to know.

The papers I refer to - they highlight that this release could be harmful for corals – in my way of thinking – its indicate that it can be useful – its only a matter of dosage. Normally – our aquariums – the bacterial community is in a state of organic carbon starving. Every molecule of useful organic carbon will be used.

Sincerely Lasse

 

[gregkn73]

The papers I refer to - they highlight that this release could be harmful for corals – in my way of thinking – its indicate that it can be useful – its only a matter of dosage. Normally – our aquariums – the bacterial community is in a state of organic carbon starving. Every molecule of useful organic carbon will be used.

Sincerely Lasse

Yes scientists don't maintaining reef aquariums, come in wrong conclusions I run a skimmerless system with 20% of DT chaeto refugium and ATS, and Donovan's denitrator https://www.reef2reef.com/index.php?threads/302685/ starting to work for me , only when I started dosing carbon in it. So our systems definitely love extra carbon. This is the reason i wonder, how much carbon are algae producing, and if those quantities are of any significance use....

 

[kecked]

Carbohydrates can be lethal. Lipopolysaccarides are some of the most toxic compounds. It seems to me that the value of a compound is the usefulness of it to the target and that’s likely different for different targets and likely good for one and bad for another.

It may also be that a constant bathing is harmful while periodic dosing is beneficial. Unfortunately we really can’t ask the targets how they are feeling.

If everyone looks happy call it a day. If not remove the degree of freedom and reobserve.

Point. I don’t think we can draw cross the board conclusions without a ton of post mortality testing for the compounds of interest and their resulting secondary met@bolites as secondary pro-metabolites from each algae. I also think there is a ton of cross interaction so you would need one species one algae and a known microfonia. Bacteria likely change the compounds too.

 

[kecked]

Ps listen to randy not me. I’m spouting off feels like info not hard data. At least I admit it.