How are your rocks so clean?

[reeferfoxx]

Correct, which would be much closer to what happens in our tanks. And they say with those conditions: "These results are in agreement with chemostat and resource‐ratios theories, which predict that organisms consume as much of the limiting resources as possible at equilibrium" which I feel is what you are arguing against.

The upper layer has N limitations that the deep layer does not. When the inflow or up current from deep waters hits the upper layer, plankton regulates the nitrates. The tides bring in the plankton and supply the nutrients. What doesn't get eatin gets regulatoed by other N and P fixers. That quote is what i'm arguing for.

 

[Brew12]

The upper layer has N limitations that the deep layer does not. When the inflow or up current from deep waters hits the upper layer, plankton regulates the nitrates. The tides bring in the plankton and supply the nutrients. What doesn't get eatin gets regulatoed by other N and P fixers. That quote is what i'm arguing for.

Except that this study does not mention N limitations in the upper layer. The model specifically states that N is not limited in the upper layer because of those nutrient inflows. I believe this is what you are referring to.

" The deep layer is inaccessible to phytoplankton because of light limitation or water column stratification. N concentrations (Na and Ni for the upper and deep layers, respectively) include nitrites, nitrates, and ammonium, and P concentrations (Pa and Pi) correspond to phosphates. The two inorganic pools are connected by physical processes—here diffusion and water vertical movements (i.e., upwellings and downwellings, governed by parameter K). Both layers have nutrient outflows to unrepresented parts of the Earth system, but only the upper layer has nutrient inflows. N supply to the upper layer (SN) includes atmospheric and riverine inflows [Cornell et al., 1995], while P supply (SP) includes only riverine inflow [Benitez‐Nelson, 2000]."

 

[reeferfoxx]

but only the upper layer has nutrient inflows. N supply to the upper layer (SN) includes atmospheric and riverine inflows [Cornell et al., 1995], while P supply (SP) includes only riverine inflow [Benitez‐Nelson, 2000]."

I'm I reading this wrong or does atmospheric and riverine conditions impact in flows? Which if there was no impact, the supply of N would always exist. No?

 

[Brew12]

I'm I reading this wrong or does atmospheric and riverine conditions impact in flows? Which if there was no impact, the supply of N would always exist. No?

I think it is more accurate to say that the supply of N will always exist in the upper layer because of those inflows.

Keep in mind that this study was on deep water phytoplankton. They modified the shallow plankton inputs to see how they impacted the deep water. I didn't see any experiment in the study on the shallow water plankton other than stating it followed the expected nutrient ratios.

 

[reeferfoxx]

I think it is more accurate to say that the supply of N will always exist in the upper layer because of those inflows.

Keep in mind that this study was on deep water phytoplankton. They modified the shallow plankton inputs to see how they impacted the deep water. I didn't see any experiment in the study on the shallow water plankton other than stating it followed the expected nutrient ratios.

Correct. But those inflows are regulated by atmospheric conditions not limited to temp or rain fall. So, with atmospheric changes, the supply of N isn't constant. That's why we have different nutrient ratios in different regions during different seasons.

The red field ratio in of itself was the theory that the ratio in plankton represented the nutrients in deepwaters. Sedement at the ocean floor and the nitrogen cycle can support that.

 

[Brew12]

Correct. But those inflows are regulated by atmospheric conditions not limited to temp or rain fall. So, with atmospheric changes, the supply of N isn't constant. That's why we have different nutrient ratios in different regions during different seasons.

The red field ratio in of itself was the theory that the ratio in plankton represented the nutrients in deepwaters. Sedement at the ocean floor and the nitrogen cycle can support that.

This study never looked at the impact of nutrients from the deep water and its impact on surface plankton.

If you want to argue that the Redfield ration is incorrect, or that it varies by location, I'll buy that. That is a much different statement than nutrient balance doesn't matter.

 

[reeferfoxx]

This study never looked at the impact of nutrients from the deep water and its impact on surface plankton.

If you want to argue that the Redfield ration is incorrect, or that it varies by location, I'll buy that. That is a much different statement than nutrient balance doesn't matter.

Some people associate balance with the 16:1 ratio. That that ratio represents no algae growth. My point is, that there is no such thing as a balance, that any increase of N or P can be regulated by fixers or organisms or people. To target a number is a preference not associated with success. That's my point, I think. You recommend nutrient availability not balance. Liebigs law of limitations supports that.

 

[Brew12]

Some people associate balance with the 16:1 ratio.

I think it is important to understand the concept of the Redfield ratio however that specific number has no value to a reefer. We have no way to measure the total available N and P in a system to make use of it. Even if we could measure it, it would have little value since it fluctuates greatly over a 24 hour period.

This is from one of the studies I posted earlier. It shows the folly of trying to maintain a specific ratio.

"Aquatic scientists have often relied on the Redfield ratio to gauge whether nutrient supplies are sufficient. Redfield (14) observed that the ratio of carbon:nitrogen: Phosphorus in marine phytoplankton was quite constant, with mean ratios by weight of ≈40:7:1. The Redfield ratio has subsequently been accepted as a general indicator for balanced growth with potential for near optimum growth rates (8). In the Experimental Lakes Area (ELA), lakes rendered eutrophic by experimental additions of N and P at N: P ratios less than Redfield ratio (7:1 weight ratio) have had N concentrations increase to above Redfield ratios as the result of N fixation by diazotrophic heterocystous cyanobacteria (2, 9, 15, 16). Algal biomass and chlorophyll a have remained proportional to P inputs regardless of the ratio of N: P added as fertilizer. Here, we describe a deliberate and extreme long-term experiment to test the effectiveness of controlling N on eutrophication."

Which is backed up further on with this.

"In a second experiment in nearby Lake 226, we deliberately tested the effects of N limitation, by adding N and C to two isolated basins, but phosphorus only to one basin (North). N: P ratios in North Basin fertilizer were 4.6 to 5.5:1 by weight, well below the Redfield ratio. Large algal blooms were again in proportion to P additions, but the responding species were primarily N-fixing cyanobacteria (2, 7)."

 

[reeferfoxx]

Perfect! So, if you suggested to me a balance of nutrients, what would that balance specifically be? Because, to have something in balance is to say its of equal weight distribution.

 

[Brew12]

Perfect! So, if you suggested to me a balance of nutrients, what would that balance specifically be? Because, to have something in balance is to say its of equal weight distribution.

I prefer to think of N and P at being on a teeter totter with some resistance in it. Not enough N and you start getting more cyano. Too much N and you start getting dino's. I consider it out of balance when your CuC can no longer keep up with the out of balanced production.

 

[reeferfoxx]

I prefer to think of N and P at being on a teeter totter with some resistance in it. Not enough N and you start getting more cyano. Too much N and you start getting dino's. I consider it out of balance when your CuC can no longer keep up with the out of balanced production.

Ok. I don't consider it the same way. I consider it as limitations rather than being out of balance. I suppose its the same difference but translated differently. The cause and effect do vary anecdotally and isn't always a rule of thumb. Though, to an extent you are correct. It just triggers me to hear balance when its an equilibrium.

 

[Brew12]

I consider it as limitations rather than being out of balance.

A limitation is just the extreme of being out of balance. Play with your system some time. Let your nitrates come up much higher than normal and look at some sump sludge under a microscope. You will likely see more dino's than normal. Drop your nitrates and you will likely see more cyano. Maybe not visible in the DT, but it is trackable.

The cause and effect do vary anecdotally and isn't always a rule of thumb.

I don't think of most of this stuff as anecdotal. The studies are pretty good. The problem is that it doesn't apply to every strain we may be dealing with. There are cyano that can thrive in high nitrogen systems. It's just that most don't.

 

[NY_Caveman]

It is nice to read and get a feeling for how you both visualize this. The analogy of the seesaw vs. the idea of limitation. Over the years in my planted aquariums I evolved to think in terms of limitation to find the balance. The concern I think I have with balance and Redfield ratio in general is that it can give the impression that minuscule amounts or large amounts are fine as long as they are in the correct ratio. For example, I never strictly followed the so called EI method in planted tanks because it just seemed wrong to avoid limits by dumping in tons of chemicals and then do a 50% water change every week.

EDIT: EI = Estimative Index

 

[Neptune1707]

My experience over the last 20 years of lots of trial and error:
1. Nutrient control/export
2. Great flow in and around rocks. Peninsula rock work helps water flow in and around tank...rock stacked against back wall creates nasty dead zones...leads to cyano and algae outbreaks.
3. Correct lighting/duration
4. Don’t overstock/overfeed
5. Use RO/DI...this was a huge discovery for me after I had fought algae of varying amounts because I was using tap water.

 

[Brew12]

The concern I think I have with balance and Redfield ratio in general is that it can give the impression that minuscule amounts or large amounts are fine as long as they are in the correct ratio.

The key is understanding the roles each play. P limits biomass. If you want to grow more or less total biomass you do that with phosphates. To shift what grows, we turn to N.
Everything in the ocean grows until it hits a limitation. Most planktonic bacteria are carbon limited. There can be many other limitations, including phosphorus. My tank is frequently iron limited. Without regular iron additions my chaeto stops growing and I start getting dino's and cyano at the same time.

 

[reeferfoxx]

It is nice to read and get a feeling for how you both visualize this. The analogy of the seesaw vs. the idea of limitation. Over the years in my planted aquariums I evolved to think in terms of limitation to find the balance. The concern I think I have with balance and Redfield ratio in general is that it can give the impression that minuscule amounts or large amounts are fine as long as they are in the correct ratio. For example, I never strictly followed the so called EI method in planted tanks because it just seemed wrong to avoid limits by dumping in tons of chemicals and then do a 50% water change every week.

EDIT: EI = Estimative Index

I followed the EI method for a few months and completely agree with you.

As far as limitations, balance, and equilibrium, the best perspective I can convey is when P is limited, N may not be(seesaw). We dose P in turn reduce N(seesaw) because of organisms(bacteria). When we stop adding and subtracting eventually we enter equilibrium(patience). The equilibrium consists of # pounds of rock, with number of fish, with number of coral, with # gallons of water, combined with organisms that increase and decrease with X nutrient(food). Equilibrium is found when we stop adding or subtracting variables to create a stable environment. As things grow, we might have to increase nutrients.

 

[Thomthom329]

The nutrient equation isnti a balance only an act. Algae of any form works as a corrector. You feed the corrector and it never goes away. Dino's more or less are an identifier to nutrient limitation. The micro organisms within the tank are regulators. This includes bacteria, pods, isopods, plankton, filter feeders, etc etc. Nutrient limitations limits microbial growth. Limit deficiencies and gain postitive diversity to out compete the uglies. Filamentous algae need help to be removed. Limiting their competitiveness limits microbial diversity. It takes time to find equalibrium but takes the headache out of creating a balance.

Like I said, it’s a balance (AKA equilibrium).

 

[reeferfoxx]

;Facepalm It's equilibrium(AKA maturity);Troll

 

[Thomthom329]

;Facepalm It's equilibrium(AKA maturity);Troll

You say tomato, I say tomato (but less elequently). I get what you’re saying but you’re arguing semantics, not context.

 

[reeferfoxx]

You say tomato, I say tomato (but less elequently). I get what you’re saying but you’re arguing semantics, not context.

Yes and subsequently semantics are important. Put into context feeding your fish means frozen food, flake food, or pellets. Semantically, each type of food impacts nutrients differently. If I said feed your plants, you assume water? But whats water without sufficient light?