Phosphorus: Algae's Best Friend

[Scrubber_steve]

Note: Organic phosphorus & in-organic phosphate. Test kits measure in-organic phosphate.

From Randy Holmes-Farley; Chemistry And The Aquarium: Phosphorus: Algae's Best Friend
(thanks; great article)

Quote -
Unfortunately for reef keepers, the world of organic phosphorus compounds is far more complex than inorganic phosphates…. the basic phosphate structure is covalently attached to the remainder of the organic molecule through one or more phosphate ester bonds to a carbon atom.

These bonds are stable for some period of time in water, but will eventually break down to release inorganic orthophosphate from the organic part of the molecule, a process that can be sped up through the action of enzymes in a reef tank.

commercial products … Typically, only reduce inorganic orthophosphate… they may not help an algae problem that is caused primarily by organic phosphates

Many organisms can enzymatically break down organic phosphates prior to absorption.

growing and harvesting macroalgae remains one of the best ways to reduce phosphate levels in reef tanks (along with other nutrients).

End


I’m thinking this is why people can have intrusive nuisance algae issues in their display, despite using commercially available phosphate removal products, & having zero PO4 readings from their test kits.

On the other hand, people who use algae filtration don’t have this problem because algae enzymes break down organic phosphorus molecules so in-organic orthophosphate can be freed & synthesised during photosynthesis. This would result in lower levels of organic phosphorus in the water column.

 

[gregkn73]

Note: Organic phosphorus & in-organic phosphate. Test kits measure in-organic phosphate.

From Randy Holmes-Farley; Chemistry And The Aquarium: Phosphorus: Algae's Best Friend
(thanks; great article)

Quote -
Unfortunately for reef keepers, the world of organic phosphorus compounds is far more complex than inorganic phosphates…. the basic phosphate structure is covalently attached to the remainder of the organic molecule through one or more phosphate ester bonds to a carbon atom.

These bonds are stable for some period of time in water, but will eventually break down to release inorganic orthophosphate from the organic part of the molecule, a process that can be sped up through the action of enzymes in a reef tank.

commercial products … Typically, only reduce inorganic orthophosphate… they may not help an algae problem that is caused primarily by organic phosphates

Many organisms can enzymatically break down organic phosphates prior to absorption.

growing and harvesting macroalgae remains one of the best ways to reduce phosphate levels in reef tanks (along with other nutrients).

End


I’m thinking this is why people can have intrusive nuisance algae issues in their display, despite using commercially available phosphate removal products, & having zero PO4 readings from their test kits.

On the other hand, people who use algae filtration don’t have this problem because algae enzymes break down organic phosphorus molecules so in-organic orthophosphate can be freed & synthesised during photosynthesis. This would result in lower levels of organic phosphorus in the water column.

I always run algae filters in my tanks, and there were times that I have algae problems. So I don't think that organic phosphorus, is just the answer to algae problem. I also used to run gfo and have 0ppb po4, but still have algae. So also inorganic phoshates is not just the answer.... currently I don't have algae problems with 0,2 ppm po4 (3ppm no3)and no gfo. In my current tank I caused algae outbreak, with overdosing Fe, so I'm pretty sure that more things, have the role, at algae outbrakes.

 

[Scrubber_steve]

My point being; gfo removes in-organic phosphate, not organic phosphorus. And test kits only measure in-organic phosphate.
So, you can have undetectable in-organic phosphate, but algae break down organic phosphorus & release in-organic phosphate using enzymes, and utilise that to grow.

Yes, there may be other reasons why nuisance algae still grows despite using algae filtration (that isn't my experience), but it is far more unlikely, for the above reason.

 

[Randy Holmes-Farley]

I wrote that many years ago, and we still have little info on the relative amounts and daily turnover of organic vs inorganic phosphate in our aquaria.

 

[Scrubber_steve]

I wrote that many years ago, and we still have little info on the relative amounts and daily turnover of organic vs inorganic phosphate in our aquaria.

Thanks for your reply Randy, but I'm not sure how to apply it to what I have suggested?

Algae enzymes break the down the bonds, releasing in-organic phosphate as a necessity.
I imagine the production of these enzymes, at any given time, is dependent on the availability of in-organic phosphate.
If available in-organic phosphate is deficient, then these enzymes become vital for the algaes existence.
So nuisance algae can grow in the display, when measured levels of PO4 are very low, by taking advantage of the enzymes.
Or, if you operate an efficient algae filter, which is an optimal environment for algae to grow in, the algae is most likely to grow in that environment, rather than in the display.

 

[Randy Holmes-Farley]

It means I do not know how important organic phosphate might be to algae or other organism growth in a reef tank.

Some portion of tanks tanks show algae growth is poor to none if compounds like GFO drive down phosphate too much.

 

[Scrubber_steve]

It means I do not know how important organic phosphate might be to algae or other organism growth in a reef tank.

Some portion of tanks tanks show algae growth is poor to none if compounds like GFO drive down phosphate too much.

So perhaps some algae can produce these enzymes, and some algae cannot?

 

[Randy Holmes-Farley]

So perhaps some algae can produce these enzymes, and some algae cannot?

That's certainly possible.

 

[Cory]

Isnt organic phosphate kind of a misnomer because all organics have phosphorus?

 

[Randy Holmes-Farley]

Isnt organic phosphate kind of a misnomer because all organics have phosphorus?

No. Most organics do not have phosphorus.

 

[ZachR32]

Isnt organic phosphate kind of a misnomer because all organics have phosphorus?

Organic phosphate meaning it's attached to carbon, I.e. An ester. Inorganic meaning in this case an ionic form, not associated with a carbon linkage..

 

[Cory]

Thanks guys! Still learning! Oh yeah I confused carbon. All organics have carbon no?

 

[Randy Holmes-Farley]

Thanks guys! Still learning! Oh yeah I confused carbon. All organics have carbon no?

Correct.

 

[Cory]

Ime trying to beat algae with po4 remover and vodka or vinegar isnt the way to do it. It creates more problems than it solves. If your using an ats thats fine too but ive starved coral with an ats. Po4 and no3 both became undetectable.

What ive found is not to worry about no3 and po4 raising, but instead to employ sea urchins. Ive tried it all, snails die too easy, algae blennys are picky, and these dont put a dent in hair algae. But sea urchins just two of them have completly cleared my rocks. Thats my solution to not starve corals.

 

[Lasse]

In nature - loss of grazers has shown to be the most important factor there the algae taking over space from corals.

Sincerely Lasse