SPS and Nitrate

[saltyfilmfolks]

The Wijgerde article is awesome btw! Bookmarked, and have read several times now. Great info!

I have another white paper on coral metabolism, I just cant find it.:mad:

 

[CastAway]

Makes me want a microscope!

 

[mcarroll]

Nutrient Links

• Ratio of energy and nutrient fluxes regulates symbiosis between zooxanthellae and corals
• Uptake of dissolved free amino acids by the scleractinian coral Stylophora pistillata
• High phosphate uptake requirements of the scleractinian coral Stylophora pistillata
• Interactions between zooplankton feeding, photosynthesis and skeletal growth in the scleractinian coral Stylophora pistillata

Those links obviously can't say all there is to say, but they say a lot.

A quote from the "Ratio..." link that summarizes things about as well as I think they could be (and I hope I'm not misattributing, but I think @Russ265 has said a version of this before...or close):

[Summarizing] the main interactions and feedback mechanisms connecting light intensity, nutrient level, and feeding in zooxanthellate corals:

1. Under constant nutrient concentration, light intensity determines the onset of nutrient limitation; as light increases, C : N ratios exceed Redfield ratios.
2. The availability of other nutrients, mainly nitrogen, determines the fate of photo-assimilated carbon. Under high C: N ratios, most carbon goes into respiration, calcification, and excreted mucus, whereas low C : N ratios favor increases in zooxanthellae density, reduce translocation, and slow down calcification.
3. Feeding on zooplankton by the coral under low light provides carbon for metabolism. Under high light it supplies both algae and animal with nitrogen.

Does that make sense and hopefully help?

I never have measurable NO3, and understand that the consensus is that this is not good for SPS.

From what I can tell, these generalizations aren't based on much if any understanding. Most folks are looking for a magical "pop" serum.

If you have fish, and feed them...and have happy, growing corals...it's unlikely you have a problem.

If you were to dose something for a nitrogen source:

• I'd suggest nitrates
• I'd suggest starting smaller than anyone tells you
• I'd tell you not to up your dose based on nitrate tests but instead to base dosage on tank conditions....and...only tank conditions.
• Do watch nitrate tests, but only to monitor for an overdose so, if needed, you can catch it and take corrective action.

I haven't had to dose nearly the amount of nitrates that I've read about some dosing, nor did I need to score a reading on a nitrate test kit before I saw results in the tank. It took a few/several weeks though. Space your changes out accordingly....give it plenty of time.

Wait wha what?? So the worse they look (in typical reefers' eyes), the better fed they are?

"worse" is a trait we're ascribing. Better fed is an objective state. So of course it can be both.

I think it's more then just the prevebial "keep things balanced" and keep NO3 at 5 and traces of NO4.

You are correct, sir!

I don't think there's anything wrong with NSW levels of NO3 and PO4.

But that does imply always-non-zero. There's always either plankton or ammonium or nitrates or amino acids or uric acid around....if not all of the above.

Just consistently and not in strong concentrations....which is where I think we go wrong.

Everything I have read so far has said browned = not healthy

See earlier comments about generalizations.

The deepest darkest growing photosynthetic coral on the planet is an SPS.

Good point!!

We could all remember that photosynthetic corals are deepwater predators of zooplankton that have recently adapted to photosynthesize.

They do not specialize in bright light – quite the opposite. Bright light is stressful to the point it can cause mortality.

It is something they cope with, not something they thrive on. (Clams, on the other hand...)

Regardless, if my SPS are starving, sunburnt and unnatural, ill take it. I want move vivid colors and accelerated growth, even if it pains them.

Ouch!

I'm going to not take you at face value since I don't think there's any good at all in making an animal suffer for my pleasure.

That does not mean they are starving, only that they are using an adaption to adjust to less nutrient rich water.

I think it can mean they are starving....trying to survive. Why mince words though?

Check out the "Interactions..." link at top.