Algae release "useful proteins, carbohydrates and metabolites."

[Randy Holmes-Farley Verified Community Expert]

That is from your Triton method description:

https://www.triton.de/en/products-services/triton-method/

"A healthy algae refuge will consume animal waste by-products and some metals while exporting useful proteins, carbohydrates and metabolites."

What is the basis for saying these these released chemicals are useful? Is there any supporting evidence?

 

[CoralWealth]

That is from your Triton method description:

https://www.triton.de/en/products-services/triton-method/

"A healthy algae refuge will consume animal waste by-products and some metals while exporting useful proteins, carbohydrates and metabolites."

What is the basis for saying these these released chemicals are useful? Is there any supporting evidence?

following along

 

[newbreefer316]

.

 

[wattson]

. Too

 

[Justfebreezeit]

Weird wording they used

 

[Randy Holmes-Farley Verified Community Expert]

Weird wording they used

Yes, I expect that is a translation issue. Most English speaking reefers would not describe release of organics from algae using the word export, keeping that term to removing things from the water or from the tank entirely. But technically, it is "exported" from the algae to the water.

 

[Justfebreezeit]

Yes, I expect that is a translation issue. Most English speaking reefers would not describe release of organics from algae using the word export, keeping that term to removing things from the water or from the tank entirely. But technically, it is "exported" from the algae to the water.

That does make sense haha. I always assume exactly what you said

 

[Mortie31]

I hope you get a reply from triton, but IMO they don’t answer many questions on the justification of there claims or methods..

 

[Cnidoblast]

I guess if something eats the algae it does

 

[NY_Caveman]

Someone from Triton was viewing the thread earlier, so maybe.

There certainly may be additional beneficial aspects of macroalgae refugia that are not fully understood.

When I ran planted freshwater tanks the plants would help outcompete algae it seemed. There was also much speculation that some plants, like hornwort, were actually producing (“exporting”) something that additionally helped to suppress algae, but to my knowledge this was never scientifically proven.

 

[Lasse]

According to DOM, DON and DOC release - this three articles can maybe be of interest. the b010p131 file is maybe the one of most importance for an aquarium fuge

Sincerely Lasse

 

[Fritzhamer]

Someone from Triton was viewing the thread earlier, so maybe.

There certainly may be additional beneficial aspects of macroalgae refugia that are not fully understood.

When I ran planted freshwater tanks the plants would help outcompete algae it seemed. There was also much speculation that some plants, like hornwort, were actually producing (“exporting”) something that additionally helped to suppress algae, but to my knowledge this was never scientifically proven.

This is extremely well documented in the freshwater world. There is a constant chemical warfare in terrestrial and aquatic plants on earth.

 

[tastyfish]

This is extremely well documented in the freshwater world. There is a constant chemical warfare in terrestrial and aquatic plants on earth.

I can give anecdotal evidence to the chemical warefare, or possibly just outcompeting each other. However, when I grew caulerpa racemosa, it rapidly became dominant over even chaetomorpha. To the point where the chaeto stopped growing and started receding, darkening in colour and becoming brittle. It was only when C.Racemosa was completely removed that the chaeto and other species grew and became healthy again.

Currently I have three/four dominant species: Caulerpa bracypus, Caulerpa serrata, chaetomorpha and a red algae which I originally thought was fauchea sp, but could be Halymenia floridana

The other algae in the refugium, including several other species of caulerpa, ulva and codium recede rapidly, even when they have no competition for light.

With regards to the release of DOC, sugars, etc. I cannot say as we cannot test for them. However my refugium is extremely stable and until recently has not been harvested at all, keeping nitrates at zero.

 

[Randy Holmes-Farley Verified Community Expert]

Folks should not misunderstand my question. I am not doubting that algae release organics.

The Triton statement asserted this was "useful", and my question was asking whether there is any evidence to support it being useful.

Since they specifically use the word "metabolite", it is worth understanding what that covers.

Many toxins contained in, and released by, algae are toxic "metabolites". Just google algae and toxic metabolites.


Examples:

Caulerpa is well known to produce and release toxic metabolites:

Preliminary survey of toxicity of the green alga Caulerpa taxifolia introduced into the Mediterranean
https://link.springer.com/article/10.1007/BF02182507

" Among the four tested compounds caulerpenyne, the major metabolite ofC. taxifolia, is the most active on sea urchin eggs. Caulerpenyne may therefore represent an ecological risk for microorganisms and the eggs of multicellular animals living close to this alga."

Chaetomorpha is has toxic metabolites in its surface to prevent fouling and potentially killing off things that try to grow on it:

Antifouling and antipredatory activity of natural products of the seaweeds Dictyota dichotoma and Chaetomorpha linoides
http://www.tandfonline.com/doi/abs/10.1080/14786419.2010.545355

"The majority of the investigations were on the bioactivity of algal metabolites and seldom has an attempt been made to address the ecological or multiple roles of algal metabolites"

"The seaweeds D. dichotoma and C. linoides exhibited activity against biofilm bacteria, inhibited byssal production and attachment in the brown mussel and deterred feeding activity in the sea angel."

And just in general, how bad the problem can be with some aglae:
Prymnesins: Toxic Metabolites of the Golden Alga, Prymnesium parvum Carter (Haptophyta)

"Increasingly over the past century, seasonal fish kills associated with toxic blooms of Prymnesium parvumhave devastated aquaculture and native fish, shellfish, and mollusk populations worldwide. Protracted blooms of P. parvum can result in major disturbances to the local ecology and extensive monetary losses. Toxicity of this alga is attributed to a collection of compounds known as prymnesins, which exhibit potent cytotoxic, hemolytic, neurotoxic and ichthyotoxic effects. These secondary metabolites are especially damaging to gill-breathing organisms and they are believed to interact directly with plasma membranes"

 

[Lasse]

Chaetomorpha is has toxic metabolites in its surface to prevent fouling and potentially killing off things that try to grow on it:

My fuge is total free of unwanted bentic micro algae - frankly - that´s one of the effect´s I want from them- If this effect also will be in the DT - I do nor know. But my fuge is located before the skimmer, the oxydator and my return pump and I doubt that these will reach my DT. And the shown toxins are anti fouling agents - not free toxins in the water column.

There is hundred of phytoplankton that will kill fish - Google red tide as an example but I do not grow phytoplankton in my fuge. Phytoplankton is one thing - macro algae is another.

Sincerely Lasse

 

[Randy Holmes-Farley Verified Community Expert]

And the shown toxins are anti fouling agents - not free toxins in the water column.

I think it is an open question whether these have remote effects:

Effects of Caulerpa taxifolia secondary metabolites on the embryogenesis, larval development and metamorphosis of the sea urchin Paracentrotus lividus
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.1016.1356&rep=rep1&type=pdf
"Experiments performed in an aquarium containing thalli of C. taxifolia showed that caulerpenyne can be released in sea water at a leve! of 2 ng ml-1 (Amade et al., 1994). In our experimental conditions, the lower effective concentration of secondary metabolites on Iarvae was 10 ng ml-1 of caulerpenyne."

Phytotoxic activity of caulerpenyne from the Mediterranean invasive variety of Caulerpa racemosa: a potential allelochemical
https://link.springer.com/article/10.1007/s10530-006-9044-2

"Even if the release of caulerpenyne in the water column could occur, its hydrophobic nature implies it would require linkage to hydrophobic compounds to affect local biota. The whitish material sampled in the aquarium at the base of a seagrass shoot may represent an example of this secretion. In fact, the chromatographic analysis of this material allowed for the identification of a typical Caulerpa marker, the pigment caulerpin, strongly suggesting that this material originated from the alga."

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, I'm not contending anything about the compounds released in refugia. I'm asking if there is an actual basis to claim they are "useful".

 

[Lasse]

I´ll turn the question upside down.

Why should not carbohydrates be useful for different microrganism and/or corals in an aquarium like mine that ´s constructed in a way to support biological processes? If you know that they are released and you know their biological importance in a living ecosystem - why can´t you claim that it can be useful ? Proteins that can be broken down to different aminoacids (by bacteria) - why should they not be useful as a nitrogen source for bacteria/corals. Instead of adding organic carbon (in this case carbohydrates) - the algae produce it - why can´t that been seen as useful?

From an ecological point of view - if you look at your aquarium from an ecological standpoint - its for me rather clear that this released compounds are usefully.

I do not know what Triton base their claim on - maybe @Ehsan@triton can clarify that but for me it make sense that my system use this released compounds in the same way as the system use the outside produced compounds of the same group (carbohydrates and protein/aminoacids) that I can buy at my LFS.

I do not run a complete Triton system, but I see my fuge as an integrated part of my system – responsible for many different tasks – there the release of carbohydrates and protein/amino acids is one important thing for at least the microbial life in my aquarium. My prove for this is that we know what macro algae release these compounds and we know how organic carbon and proteins/amino acid works in an aquarium.

Sincerely Lasse

 

[Lasse]

"Experiments performed in an aquarium containing thalli of C. taxifolia showed that caulerpenyne can be released in sea water at a leve! of 2 ng ml-1 (Amade et al., 1994). In our experimental conditions, the lower effective concentration of secondary metabolites on Iarvae was 10 ng ml-1 of caulerpenyne."

I do not know if I read this in the wrong way - but what I can understand - they have shown a release in aquaria (unknown volume of algae and aquaria) of 2 nanogram/ml (its equal to 2 micrograms/l – 2 ppb) but they say also that lowest effective concentration on larvae was 5 fold higher - 10 microgram/l -> 10 ppb. The study was done in vitro and the study did not prove any evidence (IMO) of ecological impact in the water column.

Please correct my if I have missunderstand the article.

Sincerely Lasse

 

[Cnidoblast]

perhaps the toxins excreted by c. taxifolia inhibit algae growth?? The algae inhibition would be falsely attributed to nitrate reduction! That 6,10-dodecadien-8-yne fragment of caulerpenyne looks like it could do some damage! @Randy Holmes-Farley

Still does not take away that the fragment of text on Triton website is totally meaningless and just marketing however!