Light, Alkalinity, Nutrients.

[Diesel]

Agreed, nutrients is definitely apart of it.

Something else to consider in regards to do dosing nutrients with absence of troubled algae. I've had nutrient spikes and never seen cyano, hair algae, etc., but I have seen a spike in other critters such as spaghetti worms and vermetid snails which i'm told will only thrive if and when proper conditions (nutrients) are available. I guess my point is, just because you don't have those nuisance algaes, doesn't mean the nutrients aren't there? Thoughts?

You are spot on.
My tank has the best and worst of it over the years, can I explain.............
That's why topics like this (Thank you @Dana Riddle ) and the rest for chiming in so awesome.
We just not dropping scientific language but for all to read.
IMO there are nutrients and nutrients, as we human beings have the same problem, hence even in the landscape industry and planted fresh water setups, we all wondering why??
For example, my DT was reading Po4 in and out at 0.15 for a long time as the same on No3 at 12.
Many ppl thought I had a secret, I just laughed if that came up.
But here it comes, I had no visible algae as just a bit green on the back wall, I did water changes and used 50% of my DT water that I dumped into the frag system, which is btw a separate system and 50% of new saltwater.
The frag system was setup the same as the tank, flow, lights, skimmer, sump layout and CaRx dosing.
I experienced GHA every time I did that although the numbers were close to be the same.
only thing I did different is I fed my damsels and one yellow tang different food than in the DT, when I switch to my Diesel brew that I was using on the DT no more GHA even I did a 100% WC from the DT water into the frag system.
I'm not sure if we going of topic now but if so just ban me, I'm just over excited to be back on the forum.
Mean while I just sit back and let Dana do his research on many questions and findings in this thread before we get lost in transition.

 

[Steve Ruddy]

Not ignoring anyone! I need some time to give all the material given more than a cursory review and find my old log book. But I'll throw this out for comments - do we really have have a nutrient deficiency if an aquarium is well fed? Isn't it possible that the bacterial conversion of proteins/amino acids to ammonia and hence its utilization is sufficient for zoox? That capture of particulates is enough? That 'farming' of bacteria using coral mucus supplies a constant source of food for some corals (ala Sorokin?) And that the phosphorus cycle converts enough organically-bound phosphorus to ortho-phosphate? That these might not be measurable if the conversion is relatively slow and utilization is rapid? If any of this is true, why would be add nutrients (back to my original question.) Again, I'll review your comments closely and digest the material. Be back soon!

I have never felt the need to raise my nutrient levels if they are undetectable. My corals have always grown and looked healthy anywhere between 7-11 dKH. I have experienced 2-3 dKH spikes with no tip burn.

 

[Nano sapiens]

Not ignoring anyone! I need some time to give all the material given more than a cursory review and find my old log book. But I'll throw this out for comments - do we really have have a nutrient deficiency if an aquarium is well fed?

That's a good point and IME some feel they have ULNS systems because the test kits tell them so, but in reality the systems are more nutrient rich when feeding is sufficient/regular and waste export is sufficient to halt eutrophication (I have such a system). This concept is difficult to describe to novice reef keepers.

From a historical perspective, we now have the means to keep a reef tank truly 'nutrient deficient' via much more efficient protein skimmers, high-grade GAC, GFO, Lanthium chloride, etc. than we did in the past. There are still a large number of people who equate '0' readings on a test kit (NO3 and PO4) as 'good', partially because they believe it will result in 'no algae' and partially because pristine reef waters have been shown to have very low soluble nutrients. With the methods and products available today, it is quite possible to have a truly nutrient deficient tank.

Ralph.

 

[mcarroll]

And that the phosphorus cycle converts enough organically-bound phosphorus to ortho-phosphate?

I suspect our tanks are just too clean (and/or too new) for this effect to be significant.

For example, from what I've read, detritus is both a significant alkalinity source and a significant phosphate source in the wild, but our tanks (generalizing) tend to be spotless. Likewise for the particulate carbonates in the ocean that also serve as a P repository....I doubt we have a parallel resource for any of these wild sources.

I agree that very mature tanks (I keep pointing to @Paul B but there are others too!!!) that are also very well fed are very very very unlikely to run into these issues.

Just opinion:
I honestly think that the vast bulk of "nutrient defficiencies" are due to over-use of filtration/nutrient reduction combined with starvation-feeding rates to avoid algae, and that the (premature) implementation of these tools is the real problem. These practices seem to hit new tanks especially hard. I think if folks avoided nutrient spikes, thus avoiding algae blooms, they'd be more apt to feed and less apt to use all these "tools" and get demoralized by nasty kinds of algae.

 

[mcarroll]

Why is this? Does this also depend on the coral type, flow, lighting etc?

Bleaching will always be white AFAIK. Bleaching is the expulsion of their dino's and dino's are what gives them the brownish/yellowish coloring they ordinarily have.

Browning is from an increase in dino concentration (or maybe an increase in dino cell size) and this is where nutrient history and current levels of light and flow come into play.

Locality of bleaching probably has to do with light and flow (and maybe particulate nutrient supply) in that particular location of the colony

Once they bleach, they are at risk of starving, but they are not dead. They are probably also healing from the stress/damage that caused them to bleach in the first place. If they can't acquire sufficient particulate or dissolved nutrients for repair and sustenance, they will die.

Bottom up necrosis I've read is just a re-apportioning of nutrients they already have to support new growth under nutrient limitation. Plants do something very similar under nutrient limitation too.

 

[Robthorn]

We are remembering every tank is different and none can be exactly duplicated right?

Over the many years I have experienced a lot of the issues in this hobby. Burnt tips for sure and my po4 used to always sit between .03 and maybe .05. It doesn't mean it doesn't exist because not everyone has experienced it. I don't have the big words or the memory to quote so many things I have read and experienced over the years but I do know for sure what is law in your tank is not law in mine.
I have no explanation for things that happen in some tanks and not others but I have found over the years that I am just lucky when things are going well.

 

[Grey Guy]

You guys are out of my league. I'm staying with "easy" corals.

 

[chefjpaul]

Bleaching will always be white AFAIK. Bleaching is the expulsion of their dino's and dino's are what gives them the brownish/yellowish coloring they ordinarily have.

Browning is from an increase in dino concentration (or maybe an increase in dino cell size) and this is where nutrient history and current levels of light and flow come into play.

Locality of bleaching probably has to do with light and flow (and maybe particulate nutrient supply) in that particular location of the colony

Once they bleach, they are at risk of starving, but they are not dead. They are probably also healing from the stress/damage that caused them to bleach in the first place. If they can't acquire sufficient particulate or dissolved nutrients for repair and sustenance, they will die.

Bottom up necrosis I've read is just a re-apportioning of nutrients they already have to support new growth under nutrient limitation. Plants do something very similar under nutrient limitation too.

maladaptation

 

[Randy Holmes-Farley]

I'd like to hear your thoughts of the relationships of these 3 parameters. For example, I've seen recommendations to adjust nutrient levels upwards if running high alkalinity, which seems to defy Liebig's Law of the Minimum which states the rate of photosynthesis is regulated by the least available nutrient, not the most abundant. In other words, alkalinity, acting as the carbon source for photosynthesis, doesn't matter if phosphorus is the limiting factor. Unless you're suggesting alkalinity has an effect unrelated to photosynthesis.

Sorry, I didn't read every post in this thread (and I hate it when people do that... lol). So I hope I'm not beating a dead horse.

but...

The issue is burnt tips on some SPS corals.

The hypothesis that Charles Delbeek (IIRC) stated to me:

When alkalinity is raised, calcification (skeletal growth) proceeds faster than at lower alkalinity.

If it proceeds too much faster than the coral can take up nutrients and build organic tissue, the tissue may get very thin and be easily damaged at the growing tip, either by bright lighting, or physical damage.

So the answer seems to be that if you want high growth, you need high nutrients.
If you want low nutrients for some reason (say, better color due to fewer zoox), then you may need to slow skeletal growth with "lower" alkalinity.

The lighting may come into play both from the damage perspective, the zoox perspective, and in how much energy the coral can get and use from photosynthesis.

 

[mcarroll]

The hypothesis that Charles Delbeek (IIRC) stated to me:

Thanks for posting all of that!

That agrees pretty well with more recent journal articles I've read (which don't state it so nicely) so it was a great hypothesis IMO! I wonder how (or if) he'd change the hypothesis based on that June article I posted earlier?

Unfortunately I believe that almost 100% of the nuance of Charles' hypothesis is lost in the common knowledge so there seems to be a predominant thought of high alk being "bad" and causing "burnt tips". So again, thanks for posting the whole thing!!

carbon angle again
What gets me about the carbon dosing angle I keep bringing up is that burnt tips was either unheard of or incredibly rare before carbon dosing....at least to my eyeballs and experience they were.

So when it comes to "assigning blame" for burnt tips, I've not been able to see how carbon dosing escapes culpability nor how nutrients are completely forgotten only to blame "high alkalinity". I've never understood.

I don't even understand how the finger came to point at alkalinity in first place, before anything else. High alkalinity was the norm when I set up my reef!

my reef history
11 dKH alk, 420 ppm Ca and 1350 Mg were a fairly well-agreed upon standard set of targets for a stony coral reef back then.

And being a newb at the time, I used these targets for my reef mostly going by your articles (thank you!) and generally using ideas that I could see plenty of precedent for! These numbers were not on the fringe or "new"!

Further, these targets proved to work extremely well at growing stony corals over the next five+ years – even though I hardly ever had fish in the system or fed anything. (Light was >60,000 lux at the surface from over-driven Radium halides.) It was as close as I've seen to a "true" low nutrient system that used no hacks (GFO, carbon dosing, etc) to be that way.

High alk was not an issue.

(Also I used vinegar to spike my kalkwasser and never had an issue in the tank with that either, for what it's worth.)

I will add that since setting up a doser and switching to LED's at lower lux levels, I don't really see the advantage of having alk any higher than 8 dKH....that still gives me some leeway if there's an issue like alk reagent running out, but doesn't deviate as much from "normal". There's less risk of precipitation at lower alk levels too – IMO that's the reason to run low alk, if there is one.

 

[Dana Riddle]

So if fast growth/thin tissue is the cause of 'burn', why don't we see the same occur to rapidly growing encrusting bases (often seen in recently fragged SPS corals, where the widened base acts as an 'anchor' before the corals can grow tall)?

 

[CastAway]

Ima have to re-read this thread several times, draw myself pictures, as I think there are things implied here I was never aware of. Makes my head spin.

 

[Dana Riddle]

Ima have to re-read this thread several times, draw myself pictures, as I think there are things implied here I was never aware of. Makes my head spin.

I love getting different perspectives. I, too, need to go through this thread, take notes, read references, and try to draw some conclusions. This is like the good ole FishNet days but without the flame wars.

 

[chefjpaul]

So if fast growth/thin tissue is the cause of 'burn', why don't we see the same occur to rapidly growing encrusting bases (often seen in recently fragged SPS corals, where the widened base acts as an 'anchor' before the corals can grow tall)?

Density?
Tips assuming are less dense / fragile, and as stated above exposed to higher uv and flow creating problem housing the zoox???
Are the tips growing faster than the base?
IDK anything here, like working a unexcogitable puzzle.

 

[Diesel]

Mmmm, now we also come to that point why some acros encrust like crazy before they branch out and some the opposite.
Of course the type of acro has to to with it as well.

 

[snappa1953]

I'm new to reefing but I think I'm getting some golden rules from my limited experience and lots of reading.
1. The tank is a universe with every part linked. Change one thing and everything is affected.
2. Stability is King. Corals tell you when their universe is unstable.
3. Chasing numbers breaks rules 1 and 2!
4. Pick a "Universe" - Red Sea Program, ULN, Triton, Paul B. - and stick to it. Mix them up at your peril!

This thread may have people arguing about apples and oranges.

 

[Robthorn]

Snappa there are no true golden rules that are absolutes for every tank. Except maybe once a coral is dead its dead. I can't even say that is absolute with some things I have seen in my tank and others.
Red Sea is not going to work for everyone. Neither will Zeovit. It is up to you as your own reef keeper to figure out which parts of each work for you. Its a gamble sometimes but it is how we learn.
GC I know that carbon dosing appears about the time that we started seeing burnt tips and if you remember even deformed growth tips with weird tips I can't name properly. If it wasn't so long ago I could point to some of the old threads but that was before r2r was even thought of. I think we were taking our nutrients lower than we had been before with better skimmers and carbon dosing on top of that. Not long before this we weren't even using filter socks and rapidly changing them which leads back to the original post by Dana and we have proven nothing but it sounds like it could be something. ;-)

 

[Diesel]

I love getting different perspectives. I, too, need to go through this thread, take notes, read references, and try to draw some conclusions. This is like the good ole FishNet days but without the flame wars.

Conference call with all in this thread isn't not so bad idea.
Good ole days I remember them very well.
How we ever did it 40 years ago.

 

[reeferfoxx]

I love getting different perspectives. I, too, need to go through this thread, take notes, read references, and try to draw some conclusions. This is like the good ole FishNet days but without the flame wars.

I've only witnessed bleaching and browing in connection to nutrition and not alkalinity. My only witness to alkalinity effects is a stall in growth. When alk changes "drastically" whether be 2dkh+ or less, coral seem to take a break. Growth is on pause. Only once/when levels are stable, growth continues. Then we see a change. But that change goes back to the limiting factor, is alk to high or low or nutrients? However like Dana said, a heavily and steadily feed tank wouldn't have a nutrient deficiency like you stated. And like someone else posted, tanks are different. (ie dry rock, live rock, maturity)

 

[Flippers4pups]

My question that's been rattling in my head is what is happening on the coral reef in the ocean, as compared to in our glass boxes. Let me explain......

We know that most corals uptake nutrients in two ways, through their tissue and through their mouths/polyps. Flow dependent, due to their boundary layer, "liquid" nutrients can feed the tissue as much as capturing "live" food. Or is it more "liquid" than "live". That answer is has been answered by us reef keepers, mostly "liquid".

My hypothesis is......The nitrogen cycle on the reef must be hidden low within the reef, low as in decaying matter surrounding the corals, rock and sand. Low as in the oceans flow is impeded by the corals structure, thus reducing removal of nitrates surrounding the corals to the point of not starving them?

Has there been any studies of this?