Maybe low Nitrates and Phosphates aren't the problem.

[flypenfly]

http://www.ultimatereef.net/forums/showthread.php?t=555963

 

All throughout other forums there are some highly successful tanks out there that should be a recipe for disaster in the traditional SPS thinking of a low nutrient environment. They have nitrates in the 50+ range and phosphates that are many multiples above the .03 that most people think is ideal.

 

Is it possible that it's really young tank maturity that can't support SPS with higher nutrient levels and that older systems have some magic sauce going on that we haven't discovered yet?

 

Nitrates and phosphates in the range that is considered "toxic" for SPS are usually very safe and even beneficial for every other organism in the reef. Why would SPS corals, one of the foundations of a reef evolve so differently in the same environment than all the other organisms on the very basics such as nutrient uptake.

 

I'm not saying I'm going to dump phosphates and nitrate solutions into my SPS heavy tank but it does make me wonder if the traditional view is highly flawed. Maybe ULN tanks are only required if you have a very young tank. Or maybe there's a certain ratio between light levels and nutrients and flow that we just haven't figured out yet.

 

 

http://www.ultimatereef.net/forums/showpost.php?p=5130521&postcount=49

 

Before you blame test kits, he has sent his water off to Red Sea and they confirmed his results.

 

[sunburn]

It might have something to do with their location in the wild. SPS corals are located in areas of the reef where they get violent wave action. They are constantly flushed with fresh seawater. Other corals that are located in calmer waters sit in less clean water.

 

I could be totally wrong, but it kinda makes sense.

[flypenfly]

SPS do act as a kind of barrier in a lot of reef islands but when I've been snorkeling, you can find SPS and LPS kind of everywhere in the systems.

[Chrisl1976]

Are we fragging and tank raising our way to greater flexibility in the parameters? Perhaps the multiple generations of propegated corals are developing a resistance.

[flypenfly]

I think some of those may be several years old frags (20+).

[NanoPoseidon]

I think its like most things in this hobby... Very Subjective. Even in doing research, you find very contradicting paths to the same end result (What is a complete killer in one tank ends up thriving in another). Creatures (even corals) have different methods of adaptation and some survive and thrive, some don't.... Seems to be the way of the world! I think it kinda adds to the splendor, that is Reefing...

 

My 2 cents

 

NP

[wombat]

The need to keep phosphates so low is highly overblown.

 

 

 

This is Joe Yaiullo's 20,000g reef tank in Long Island. Phosphate stays around 0.15-0.20 ppm consistently and has for years. Obviously the corals aren't reading all the posts that say this is a problem.

 

The only person in the world who is able to consistently grow large colonies of Acropora palmata in captivity, Bill Hoffman at the Ft Pierce Smithsonian Marine Institution, is doing so in a tank with a consistent phosphate concentration between 0.20-0.25 ppm.

 

There are many more examples like this but these are two of the most noteworthy.

 

IMO nitrate above about 10-20 ppm maximum is a sign of bigger problems than "elevated" phosphate.

[uglyfish]

The need to keep phosphates so low is highly overblown.

 

I see mature reefs running higher numbers with success, but it's not a success I share (with my 1 year old setup). When my phosphate levels go to 0.06ppm my tank turns into a hairy green mess... how do you keep po4 at 3x that level without an algae outbreak? Maybe my 0.06 ppm po4 is the sweet spot for growing algae and if I just let my po4 rise to 0.2ppm the algae will die off and everything will be ok...?

[wombat]

I see mature reefs running higher numbers with success, but it's not a success I share (with my 1 year old setup). When my phosphate levels go to 0.06ppm my tank turns into a hairy green mess... how do you keep po4 at 3x that level without an algae outbreak? Maybe my 0.06 ppm po4 is the sweet spot for growing algae and if I just let my po4 rise to 0.2ppm the algae will die off and everything will be ok...?

 

Herbivores.

 

Even "ultra low nutrient" reefs in the wild will become overgrown with algae if the herbivores are removed. The trick in an aquarium is to balance the amount of growth with the amount of grazing. Mature tanks in many cases will have a higher population of copepods and other micro grazers as well as larger areas where coralline algae has taken over, limiting the areas where nuisance algae can take hold. A healthy population of copepods can have a serious impact on algae growth in a reef tank. It is also possible that some other nutrient, say iron for instance, is limiting the growth of algae in those tanks with a "high" phosphate concentration.

 

A lot of recent studies have made us rethink the role elevated nutrients play on a reef--it is not so much the dissolved nutrients that harm corals but the downstream effects they *sometimes* cause. Mostly algae overgrowth. In some cases elevated nutrients appear to benefit corals and lead to faster growth.

[wombat]

And I should add that there is almost certainly some point at which the concentration of phosphate or nitrate alone can start to harm corals. It certainly doesn't hurt to keep these numbers low, but there is plenty of evidence that corals will thrive, spawn, look great, etc. at concentrations much higher than some folks consider tolerable.

[flypenfly]

It seems a common feature among high nutrient tanks that sustain high end growth is maturity. It seems ULNS I read about are relatively young. Perhaps that is the only way to get high end growth in those systems and that is how the tank grows and it never develops correctly.

[uglyfish]

A lot of recent studies have made us rethink the role elevated nutrients play on a reef--it is not so much the dissolved nutrients that harm corals but the downstream effects they *sometimes* cause. Mostly algae overgrowth. In some cases elevated nutrients appear to benefit corals and lead to faster growth.

 

I read http://reefbuilders.com/2011/12/05/acropora-phosphate-growth/ this article about high po4 and faster growth & lower skeleton density - which concurs with the tanks of higher po4 with good acro growth.

 

So the "magic sauce" is made up of a thriving micro-critter population along with an efficient herbivore community.

 

The link to the thread in the OP is very interesting - especially the posts about going from high nutrient to low nutrient and only then experiencing byropsis and cyano outbreaks...

[metrokat]

The need to keep phosphates so low is highly overblown.

 

 

 

 

 

This is Joe Yaiullo's 20,000g reef tank in Long Island. Phosphate stays around 0.15-0.20 ppm consistently and has for years. Obviously the corals aren't reading all the posts that say this is a problem.

 

The only person in the world who is able to consistently grow large colonies of Acropora palmata in captivity, Bill Hoffman at the Ft Pierce Smithsonian Marine Institution, is doing so in a tank with a consistent phosphate concentration between 0.20-0.25 ppm.

 

There are many more examples like this but these are two of the most noteworthy.

 

IMO nitrate above about 10-20 ppm maximum is a sign of bigger problems than "elevated" phosphate.

Wombat, why is high phosphate not causing browning SPS in these tanks?

[Nano sapiens]

One thing to remember is that we are only testing for inorganic phosphate and not all the other forms that phosphate comes in. It's kind of like knowing the amount of one ingredient in a cake, but being clueless as to how much of the other ingredients are in there.

 

If one looks at a typical offshore reef the levels of all nutrients in the water itself are very, very low. The photosynthetic corals are getting glucose, glycerol, and amino acids from the Zoanthellae and the carbon needs are coming from other organic sources (zooplankton, phytoplankton, detritus, marine snow, etc.). There is a lot more 'food' available per given area on a reef than in our tanks so the coral's energy needs can be met, along with sufficient sunlight.

 

Corals are adapted to take advantage of a multitude of sources to supply their metabolic needs. The sum total is what's important, so as long as a system is supplying the energy that a coral needs for health and growth, without stimulating excessive algae growth, it's all good.

 

ULNS systems attempt to mimic the nutrient poor water conditions found in nature while at the same time supplying the lighting and nutrients required for corals to thrive. Interesting challenge to keep water so pristine and yet still provide high coral nutrition levels (additives). Insufficient nutrients for the corals is why we have the often reported 'Pale Corals'.

[Nano sapiens]

Wombat, why is high phosphate not causing browning SPS in these tanks?

 

Not Wombat here , but the article did mention browner areas in the corals subjected to higher phosphate:

 

It is believed that these Acropora grew faster with increasing phosphate level due to a higher concentration of zooxanthellae, which was also noticeable in the coloration of the corals in the separate treatment groups. Although all the corals started off the experiment with strong presence of white growth margins at the axial tips and the base, in the high phosphate group the growth margins were mostly brown whereas the low phosphate group still had noticeable white margins.

 

I wonder if they had run the experiment longer if they would have noticed even more browning-out

 

 

[wombat]

Wombat, why is high phosphate not causing browning SPS in these tanks?

 

Wish I could answer that with any degree of certainty! What exactly causes corals to color up is the $100,000 question.

 

My gut tells me that the brown zooxanthellae is there, but masked by high levels of pigments that are produced by very healthy corals under lots of light.

 

 

One thing to remember is that we are only testing for inorganic phosphate and not all the other forms that phosphate comes in. It's kind of like knowing the amount of one ingredient in a cake, but being clueless as to how much of the other ingredients are in there.

 

If one looks at a typical offshore reef the levels of all nutrients in the water itself are very, very low. The photosynthetic corals are getting glucose, glycerol, and amino acids from the Zoanthellae and the carbon needs are coming from other organic sources (zooplankton, phytoplankton, detritus, marine snow, etc.). There is a lot more 'food' available per given area on a reef than in our tanks so the coral's energy needs can be met, along with sufficient sunlight.

 

Corals are adapted to take advantage of a multitude of sources to supply their metabolic needs. The sum total is what's important, so as long as a system is supplying the energy that a coral needs for health and growth, without stimulating excessive algae growth, it's all good.

 

ULNS systems attempt to mimic the nutrient poor water conditions found in nature while at the same time supplying the lighting and nutrients required for corals to thrive. Interesting challenge to keep water so pristine and yet still provide high coral nutrition levels (additives). Insufficient nutrients for the corals is why we have the often reported 'Pale Corals'.

 

 

 

Very good post. There should be tests to determine organic phosphate in saltwater for hobbyists if there aren't already. It would be useful to know.

 

The "ULNS" tanks I have seen all look pretty to me, but nothing like what corals on a real healthy reef look like. They look like a reef after a bleaching event!

[wombat]

Here is a good shot of the healthiest "SPS" type reef I've been on. It's in Kwajalein Atoll, Marshall Islands, and this is in about 5' of water. There were city block sized areas of reef there that were a monoculture of a single Acropora species with the occasional bit of purple Montipora peeking out from the "understory".

 

[Nano sapiens]

Very good post. There should be tests to determine organic phosphate in saltwater for hobbyists if there aren't already. It would be useful to know.

 

The "ULNS" tanks I have seen all look pretty to me, but nothing like what corals on a real healthy reef look like. They look like a reef after a bleaching event!

 

In the natural system dilution of nutrients is assured due to a 'water change every second', so to speak To attempt to supply as much nutrition as available in nature, while still keeping the water just as clean and the system free of nuisance algae...that's a tough one. It's no wonder that many ULNS systems have corals that are 'pale pastel' in their coloration since they are often in need of more nutrition than provided by the aquarist.

 

Whoops, I think I repeated myself here. One of the idiosyncrasies of advancing age

[metrokat]

So all I'm understanding is what I've always understood. A balanced system is needed. For some that means no water changes with massive macro fuges for nutrient export. For others it is pristine ULNS with or without supplemental feeding, for others still it is weekly water changes, fuges, reactors, skimmers. Whatever you choose to do, there is no right or wrong way.

 

There are indications when something goes awry like browning or bleaching corals, algae blooms etc, at which time steps should be taken to correct the problem which is indicative of imbalance.

 

So what was this thread about again?

[uglyfish]

Very good post. There should be tests to determine organic phosphate in saltwater for hobbyists if there aren't already. It would be useful to know.

 

I need an education on the difference between organic and inorganic phosphate... I though organic phosphate was bound to a plant while inorganic phosphate was floating around waiting to be bound. So - the plant consumes inorganic phosphate and once consumed, it becomes organic phosphate... plants don't consume organic phosphate because organic phosphate is already tied up in another plant.

Snails eat the plants (organic phosphate) - plants take the inorganic phosphate floating in the water. That's why I thought we don't measure organic phosphate. Do I have this wrong?

[Nano sapiens]

Here is a good shot of the healthiest "SPS" type reef I've been on. It's in Kwajalein Atoll, Marshall Islands, and this is in about 5' of water. There were city block sized areas of reef there that were a monoculture of a single Acropora species with the occasional bit of purple Montipora peeking out from the "understory".

 

 

Wow, 'natural monoculture' with a sprinkling of Montipora 'weeds'

 

The healthiest reef system I've ever seen was in a protected area of Palawan, Philippines, in the late 1980's. In relation to coral energy needs, I remember the plankton swarms were so dense, especially in the afternoon, that it was like swimming through a fog bank. The amount and quantity of food organisms washing the reefs everyday was amazing.

[Nano sapiens]

I need an education on the difference between organic and inorganic phosphate... I though organic phosphate was bound to a plant while inorganic phosphate was floating around waiting to be bound. So - the plant consumes inorganic phosphate and once consumed, it becomes organic phosphate... plants don't consume organic phosphate because organic phosphate is already tied up in another plant.

Snails eat the plants (organic phosphate) - plants take the inorganic phosphate floating in the water. That's why I thought we don't measure organic phosphate. Do I have this wrong?

 

Phosphate cycling is quite complex and we've made it even more complex by giving different names to the same thing, but in a nut-shell 'inorganic phosphate' (aka PO4 or orthophosphate) is primarily utilized by algae and plants while 'organic phosphate' is used by animals. Animal foods we feed are primarily organic phosphate. However, bacteria can convert organic phosphate into inorganic phosphate, so excess food/detritus often ends up fueling algae blooms. Algae store inorganic phosphate in their tissues so that's why its so important to harvest the growing algae to remove this form of phosphate from the system. Decomposition of the algae is the worst case scenario as you can well imagine since the inorganic phosphate then becomes available to other algae in the system causing increasing eutrophication.

[uglyfish]

Phosphate cycling is quite complex and we've made it even more complex by giving different names to the same thing, but in a nut-shell 'inorganic phosphate' (aka PO4 or orthophosphate) is primarily utilized by algae and plants while 'organic phosphate' is used by animals. Animal foods we feed are primarily organic phosphate. However, bacteria can convert organic phosphate into inorganic phosphate, so excess food/detritus often ends up fueling algae blooms. Algae store inorganic phosphate in their tissues so that's why its so important to harvest the growing algae to remove this form of phosphate from the system. Decomposition of the algae is the worst case scenario as you can well imagine since the inorganic phosphate then becomes available to other algae in the system causing increasing eutrophication.

 

Right... so how would you test for organic phosphate?

[Red_Blenny]

How about the Redfield Ratio? I recall that if you keep Nitrates and Phosphate at a certain level where there balance each other, then the corals wouldn't try to gain/lose zooxanthellae.

[uglyfish]

How about the Redfield Ratio? I recall that if you keep Nitrates and Phosphate at a certain level where there balance each other, then the corals wouldn't try to gain/lose zooxanthellae.

 

I'm not sure it works that way...