the secret to colorful,healthy corals....obvious to some,elusive to many

Can rock absorb phosphates deep into its pores?

Yes, that where it goes.

If so I am assuming that I can't cook the live rock(acid then chlorine baths)

You can, but this kills all the periphyton on the surface, and all the life inside, and all the natural filtering and food production they were doing for you. It will take a few years for it all to grow back.

So should I replace this rock entirely?

You don't need to, if you just increase your exports. Your rocks have probably been absorbing your excess imports up until now; they can't do it any more. Do some serious export, and your phosphate (however much there is) will come out, and you'll keep your periphyton and live rock alive.
 
Yes, that where it goes.

Why only in the pores? If it absorbs phosphates, than it should be absorbing it everywhere that has access to the phosphates.

You don't need to, if you just increase your exports. Your rocks have probably been absorbing your excess imports up until now; they can't do it any more. Do some serious export, and your phosphate (however much there is) will come out, and you'll keep your periphyton and live rock alive.

Export how? What form of P are we trying to export?

Doesn't the periphyton pull the P from the LR? Isn't that what "cooking" the LR is doing? Isn't this going on all of the time?

G~
 
I just meant throughout the inside of the rock, like a sponge.

Any export is export. Inorganic phosphorous (as PO4) is what you want to remove.

Periphyton does eat inorganic phosphorus as it comes out of the rock, as well of from the water column. It converts it into glucose as well as living tissue, which then feeds the animals (especially pods for mandarins).

Cooking is unrelated to any of this.
 
I just meant throughout the inside of the rock, like a sponge.

I have heard from some people that this is an equilibrium reaction and not a binding reaction. If it is an equilibrium reaction then how can it be like a sponge? Shouldn't it always be in equilibrium with the water column? the calcium carbonate could not become full of PO4 if it stayed in equilibrium with the water column, correct? Everything i read about calcium carbonate is that it is a phosphate binder, so that would point to it behaving like a sponge.

Any export is export. Inorganic phosphorous (as PO4) is what you want to remove.

Where does all of the inorganic phosphate come from if it is being absorbed by the calcium carbonate? Animal waste products contain both inorganic and organically bound P. What do we do about the organically bound P?

Periphyton does eat inorganic phosphorus as it comes out of the rock, as well of from the water column. It converts it into glucose as well as living tissue, which then feeds the animals (especially pods for mandarins).

How is the PO4 coming out of the LR if it is being absorbed by the calcium carbonate?

Cooking is unrelated to any of this.

What if it is related? What if the periphyton removes the PO4 from the calcium carbonate and makes it available for the rest of the organisms in the system? Doesn't something have to release the PO4 from the calcium carbonate in order to make it available for higher organisms?

G~
 
Learned a lot and am testing some of the theory contained here. Dropped my alk from 9 to 8 with further drop planned.
 
I really think there is a "Sweet Spot" that needs to be found and its very difficult to lock in our tanks for long periods into the spot. I notice my tank will hit it for a few months then fall out then back in.
Let face it, we don't feed our tanks the "Exact" amount every day, there are just sooo many variables.
 
I've never really understood the arguments about raising one parameter and dropping another to accelerate growth or improve colouration.
In what conditions are corals at their healthiest and most vibrant......in their natural environment.
Natural reef conditions are roughly:

Typical Surface Ocean Value:1
Calcium 420 ppm
Alkalinity 7 dKH
Salinity sg 1.025-1.027
pH 8.0-8.3
Magnesium 1280 ppm
Phosphate 0.005 ppm
Ammonia <0.1 ppm

So why aren't these the figures we aim for? Coupled with intense lighting of course. Using a quantum meter I measured about 1850 PAR on the ocean surface on a winter's day here in Western Australia. My tank has a PAR reading of 650 at the water surface. Obviously it goes without saying that the sun has to penetrate further into the ocean but the intensity is higher than anything we can replicate in our homes.
So I believe that by trying to match the natural parameters and having intense lighting at the correct colour spectrum which is spread through the tank will give you the best chance of success.
 
I've never really understood the arguments about raising one parameter and dropping another
I agree in the sense that corals have adapted as well as they can to those environments, though I'm not sure their goals are the same as ours. Like, is their adaptation geared toward producing color and growth, or some characteristic more useful to them in nature that isn't required in captivity (idk, maybe hurricane resistance, or something about spawning)?

Also, a natural diet doesn't always provide the best of everything. A good example is folic acid. Before we figured out prenatal vitamins, having a baby be born with its spine on the outside was just one of those things that happens if you have bad luck. Now moms take a pill with no side effects that jacks up their folic acid, and the bones stay on the inside. It's an unnatural tweak of one parameter that significantly increases viability. It would stand to reason that when we are trying to get things to grow fast and be pretty, there might be an analog in our tanks if we can control for side effects.
 
IF, and thats a big if, If the rock had phosphates it would have a limit as to how much it would excrete until it reached equilibrium and it begs the question as to why suddenly it switched from adsorbing to leaching and why then it would persist in leaching.

My daughter has a 36 Nuvo and it has fabulous corals and my tank isn't too shabby either. I think if you have an algae problem it's no different than any other algae problem. You need to find a balance. Either you have too much input, not enough biology, or not enough export.

It's not the rocks, or so that's what I think ;)

I agree. I can't imagine it being some sort of equilibrium thing whereby the rocks are only leaching phosphates 'now', as opposed to 'before' when it is taking up all the phosphate.

My view is the same as yours, pretty much. One minor different. 'Too much input, filtration not up to par, or not enough export'. Though essentially, it is 'not enough biology'. And I agree that it has to be a balance of all three. It's not good enough to blame any one of them all the time, and the cause really needs to be identified. Every once in a while I would see a post about algae, and invariably there would be that 'you are feeding too much' post. Scroll up, and half the time the amount of feeding mentioned is already too low. >_<
 
Just a Few Side Notes
I'm just now making myself aware of high PO4 in my system that my scrubber cannot handle alone. So GFO will be attempted to get parameters closer to what 'may' yield better results.

GFO should solve the problem in the short run but if your ATS is there to get rid of excess waste then I think that you should also go back and look at your ATS to see if it is undersized, has too little flow or light. The more variables that you add to a tank, like other export methods, the harder it is to diagnose and keep stable.

When I hear that someone is having issues with P and not N, I think that PERHAPS the ATS is nitrate limited and there are threads for that, primarily for people with skimmers that are dosing Vodka but ATS users can have the same problem. I had them when I tried vodka.

As for waste exports, I think that if you had a good enough skimmer and plenty of GFO, you would not have to worry much about poo. [Of course you want to get rid of as much as you can. (repeat)]

The reason that I say that is that I had tank with a well designed ATS and a popular version of a Jaubert sand bed with a plenum. As I have detailed in other threads, the solid waste was processed.

I could see into the open water volume at the bottom of the tank that was stagnant. On the glass, I had placed a coated magnet so that I could move it around. In the first month there was a ¼ inch fine layer of gray dust like detritus that formed on the bottom. Eight years later that layer never got any thicker than that same ¼ inch. It had to be different dust.

I was growing filter feeders. I put food in the tank daily that was measured in spoons and ½ cups, not cubes. The poo, un-used powdered foods, living and dead bacteria, fish foods, fish fertilizer and many other things went somewhere.

Between my export and tank processes my N and P where hardly ever even detectible. I would suggest that food web processed it. Dr. Adey wrote a lot about this web in his book in the early 90's. Recent studies are showing that the web is much bigger and more complicated than we thought and is still, little understood.
 
.....in their natural environment.
Natural reef conditions are roughly:

Typical Surface Ocean Value:1
Calcium 420 ppm
Alkalinity 7 dKH
Salinity sg 1.025-1.027
pH 8.0-8.3
Magnesium 1280 ppm
Phosphate 0.005 ppm
Ammonia <0.1 ppm

So why aren't these the figures we aim for?

But that's exactly what many of us do. In fact if you look through the TOTM list you'll find some amazing tanks with great color and those parameters.

I use all NSW here is Southern California, have done so for nearly 30 years and only raise Alk slightly above it's typical value to 7.5 because I use KW to stabilize pH at night. SPS grow just fine and have very good color.

Coupled with intense lighting of course. Using a quantum meter I measured about 1850 PAR on the ocean surface on a winter's day here in Western Australia.

I get just under 2000 here as we pass the Summer Solstice which the Clear Sky Calculator confirmed was an accurate reading with my Apogee PAR meter.

Obviously it goes without saying that the sun has to penetrate further into the ocean but the intensity is higher than anything we can replicate in our homes.

You apparently don't know anyone with the latest ATI LED powermodule. While you can achieve near daylight values in excess of 1900 PAR with it I've only seen people running them at 1200 :eek2:
 
I have heard from some people that this is an equilibrium reaction and not a binding reaction. If it is an equilibrium reaction then how can it be like a sponge? Shouldn't it always be in equilibrium with the water column? the calcium carbonate could not become full of PO4 if it stayed in equilibrium with the water column, correct? Everything i read about calcium carbonate is that it is a phosphate binder, so that would point to it behaving like a sponge.

Where does all of the inorganic phosphate come from if it is being absorbed by the calcium carbonate? Animal waste products contain both inorganic and organically bound P. What do we do about the organically bound P?


G~
It is both a binding and equilibrium reaction
In some cases the phosphates bound up in rocks can support algae for 6 months or longer. If the rock is so bound up esp on the surface then it loses its effectiveness in providing a location for denitrifiers within its core
In these cases I dump the reef rock and replace it with dry rock eg Florida key largo.
 
Using a quantum meter I measured about 1850 PAR on the ocean surface on a winter's day here in Western Australia. My tank has a PAR reading of 650 at the water surface. Obviously it goes without saying that the sun has to penetrate further into the ocean but the intensity is higher than anything we can replicate in our homes.

I had a LED retrofit kit for my biocube 14 that was Steves Extreme kit plus 6 more violet LEDs, when turned to 100% I got 3000PAR 2" under the water (which had SPS growing that high) with apogee meter even with the violets underrepresented in that number, so it's possible to get some big numbers. That being said the SPS did the best, color and growth, in about 300-400 PAR for me. Just my experience with that much light - no matter the acclimation none of the coral improved with higher light levels than that for me.
 
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Using a quantum meter I measured about 1850 PAR on the ocean surface on a winter's day here in Western Australia. My tank has a PAR reading of 650 at the water surface. Obviously it goes without saying that the sun has to penetrate further into the ocean but the intensity is higher than anything we can replicate in our homes.
So I believe that by trying to match the natural parameters and having intense lighting at the correct colour spectrum which is spread through the tank will give you the best chance of success.

I dont totally disagree...but I dont think it matters what the PAR is at the surface. I am more interested in what the PAR is where corals are growing. Also...IMHO, I dont think PAR matters so much, however its all most of us (including me) can measure. Its PUR that corals care about.

I know that some LED emitters in our fixtures can have a fairly high PAR and near zero PUR. So in a way, PAR meter readings need to be taken with a grain of salt. PAR meters can provide us with some very meaningful information and at the same time completely useless data.

Hart24601 has a point. I dont think many of us are helping our corals one bit by blasting them with tons of light. Corals are amazingly adaptive and will do well under countless conditions (given time to adapt), have great colors and good growth. You can see that in some of the many tanks here that range for ULNS to high nutrient tanks and have lighting from very intense to what some would call low for the corals that they have.

So...what to do? Maybe its moderate lighting for corals like SPS in the 300-400 PAR range with the appropriate spectrum of course? With higher light intensity than that I think most corals (not all) are/have just adapting to what we provide them.
 
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Most reefers run a fairly constant light level over a long day. 12 hours might be a typical day for many. Some tanks have a ramp up and ramp down period of 1 hour each but normally, the lights are on most of the day.

I have a weird theoretical question but I think that it is close to being on topic. !IF! you had a light that moved over a long tank as the day progressed, what kind of par would you want? What kind of intensity would the corals tolerate? Or, if you had extra lamps that you could turn on for only two or three hours, Or, if you could turn your LED's way up for a short period of time, what kind of intensity would work well.

Does anyone know how fast light levels rise and then fall off again in the ocean, only one or two feet deep? Lots of companies successfully grow corals in tanks that are several inches deep to only few feet deep, in full sun only. Despite the depth that these corals are typically collected, many of them grow quite well in depths that are similar to our tanks.

I know that some indoor coral farmers use motorized light tracking but I think that they do it to save money over large areas. In a six foot tank for example, one lamp could easily be too strong, even when moved.

The reason that I ask is because I plan on building an LED system that I can turn up and down as well as move over the tank during the day.

In the past I built a moveable system for two 250 watt metal halides so I want to do it again. I am mainly doing it for cosmetic reasons, not for the corals. I just think that it will be more interesting to have the lighting change during the prime viewing hours. Never the less, I might be able to take advantage of this feature to grow better corals.

So has anyone played with changing the intensity of the lights for the corals?
 
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