Maybe low Nitrates and Phosphates aren't the problem.

[Nano sapiens]

Love the discussion on the thread! Mental reef sex!

 

 

LOL...not sure I want to 'go there'...

 

Compared to 30/40 years ago we know a whole lot more, but you are right that there is always more to learn around the corner. The question of why does something work should have a concrete scientific answer and if we don't have one then we need to investigate further. A really positive trend I've seen lately is hobbyist anecdotes and observations being tested using scientific methodology and scientific articles becoming more accessible to hobbyists. Both groups can contribute to the overall knowledge of aquatic systems.

[flypenfly]

If my GFO overdose taught me anything, is that there is such a thing as too low of phosphates.

 

I also had a huge GFO overdose but it crashed my alkalinity more than anything.

[flypenfly]

Hard to deny the man's corals look very healthy with crazy off the chart phosphates

 

http://www.ultimatereef.net/forums/showthread.php?t=161687&page=13

[WalrusKisses]

I would be really interested to see the dissolved oxygen to phosphate/nitrate ratio in some of these SPS tanks with "high" nutrients. My thinking is that younger tanks, without a stable mix of bacteria and micro-fauna/flora, end up suffering from low oxygenation as these organisms metabolize nutrients and take up oxygen in the process (also leading to higher levels of carbon dioxide). Perhaps in larger and more mature systems, for whatever reason higher nutrients do not necessarily lead to these problems.

 

TL;DR Maybe high nutrients aren't terrible, but byproducts of the organisms that use them are.

 

I also see potential in what some others have proposed--that successful generations of tank raised coral are becoming more tolerant of our tanks' chemistries. It makes sense that corals able to live through not perfect conditions, or even flourish in them have a better chance of being fragged and staying in the hobby. Sort of a weird not-so-natural selection perhaps

[farkwar]

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".

 

I certainly would not be in this hobby, if a healthy tank was only full of brownish green acro.

 

What we can make the coral look like, under our control, appears to be not far off from dog breeding. And while humans have certainly bred disease into their selections...most would not want a true healthy wild "dog" before humans changed them on purpose, ie a wolf.

 

Im going to be starting my current systems with the Zeo methodology. Certainly not for the easter egg reef. I hope there is some neutral ground between keeping a dirty tank and a box of easter egg colored coral.

 

They remind me of the dead bleached and dyed colored coral people used to have in the 70s.

 

Anyway, my main attraction to the Zeo method is really removing Ammonium and Ammonia from the system before denitrification. And the idea of "feeding" coral bacteria is appealing as well. Ammonia is definitely toxic to life, nitrate and phosphate is much more tolerated. Nitrogen is required for most of the important workings inside a cell(dna rna proteins etc), phosphorus is required to build cell membranes.

[Nano sapiens]

Looking to nature, it is interesting to note that a typical Coral Reef has many varied micro environments: some with higher nutrients in the water column and some with very little. It is not uncommon to find the same or similar species doing well in a variety of different locations so this indicates that corals are, for the most part, adaptable. Of course, some corals will do better in one type of environment vs. another.

 

Speaking to higher nutrient loaded systems in a mature captive environment, I believe that the number and type of bacteria play a very important role in addition to sufficient herbivory. If the system stays at a 'steady state' then a balanced equilibrium is achieved and the system thrives. Problems occur when the rates of nutrients, light intensities and other factors fluctuate widely. Also, nutrient levels increasing steady beyond the ability of the system to effectively deal with them is detrimental as is a substantial decrease of nutrients to the point where the various organisms' metabolic functions can't be properly maintained.

[coralcolors]

I have gleaned much information from this thread. I am new to reef aquaria but have had a bit of a struggle with my relatively young system. While my nutrient load is not especially high, I have been struggling with controlling hair algae in this young tank. I have concluded that the age of the tank is indeed an important variable in maintaining the health of corals. While my nitrate is 0.75 and phosphate 0.04, I have hair algae and very poor coral growth and color....I'll keep trying. Thanks for the information posted here.

Gary

[flypenfly]

There's also old tank syndrome..

[SantaMonica]

Here is a copy of my post on the OP link:

 

"Algae is known to give off glucose (DOC), which of course is basically carbon dosing. And corals are known to control the environment of zoox. And finally, corals are also known to have a very high microbial layer surrounding their tissues.

 

My conclusion is that the corals use the "carbon dosing" of the zoox to grow heterotrophic microbial concentrations next to the polyps such that the polyps can then consume the microbes to obtain nitrogen. The thin-layer microbial community is carbon-limited, and thus they form around the nearest source of carbon which in this case is the coral itself. The coral knows this and controls the zoox' environment so as to give off enough carbon which will generate a suitable amount of nitrogen prey around it.

 

This would explain why the density of corals (one coral next to another, as in a reef) generally survives better than a lone coral."

 

So what I am saying is that is looks like coral density is the driving factor (closeness of one coral next to another)

 

As for organic P, it is just food.

[Nano sapiens]

The interrelationships that corals have with other organisms (and the effects, therefrom) are still being explored: Consider this class of Protists and all the fatty acid substances they can make available to corals (HUFA, PUFA, MUFA, and DHA).

 

http://www.reefs.com/blog/2013/08/26/thraustochytrids-the-coral-symbiont-everyone-should-know-part-1/

http://www.reefs.com/blog/2013/08/27/thraustochytrids-the-coral-symbiont-everyone-should-know-part-2/

http://www.reefs.com/blog/2013/08/28/thraustochytrids-the-coral-symbiont-everyone-should-know-part-3/

http://www.reefs.com/blog/2013/08/30/thraustochytrids-the-coral-symbiont-everyone-should-know-part-4/

 

Quote: 'Several studies have found greater than 90% of the organisms living in the mucous of the coral sampled are from Thraustochytrids'.

 

Quote: 'The coral provides the main limiting nutrient, carbon, in the form of glucose and other sugars (originally produced by the corals other symbiont, zooxanthellae), to the Thraustochytrids, who then utilize sulfur and other elements from their surroundings to grow and produce fatty acids and vitamins, which the coral then consume continually throughout the day.'

 

Consider that we now have zooanthellae (dinoflagellates), various bacteria and protists all functioning symbiotically within and on the coral. Each one produces it's own subset of 'waste products' which are then continuously used as food by the others. I'm sure there will be more surprises as studies continue (such as the exact roles that various viruses play in the life of a coral).

[flypenfly]

Another example of a high nutrient tank that shouldn't be doing as well as it is

 

http://www.reefcentral.com/forums/showthread.php?t=2366953

[flypenfly]

Several years later, we are still arguing about it but people aren’t chasing nutrient levels like they used to.