Nutrient control question......
- Thread starter Gwitness
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A reef tank can be run very simply (LR, LS & WCs) and do remarkably well, no matter what the size. The caveat is that in very basic systems the hobbyist has to have an effective maintenance plan (and be consistent with it) along with regular water changes (unless one is implementing Triton or similar) to promote optimal water conditions over the long term. Striking a proper balance between nutrient input and export is vital as well as an appropriate crew of herbivores to help keep most nuisance algae in check (some types of algae can require more drastic measures).
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Gwitness
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I agree 1000% BUT my thing is that I do all of this and I definitely don't over feed and I have no idea how my nutrient import and export got out of whack to begin with?? But maybe I never had enough live rock to begin with or something so that is why I'll be adding about 45 more pounds or so
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Gwitness
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Yeah for sure...
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Gwitness
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I mean in the meantime before I get more live rock should I just do a ridiculously huge water change??? Or do like 2 40 gallon water changes this week or should I just let it be right now and keep doing my normal routineBut still fighting this!!! Hahaha
Damon
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I would, since your skimming, do like randy said and just cut down on your dosage.. You could get more rock, but you run the risk of adding additional nutrient with the inevitable die off..
That is the wait it out method I would do.. Or... Lol, you could go the immediate and easy route of chemiclean and be done. But that's not addressing the root of the problem..
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Gwitness
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Lol yeah that doesn't sound like a bad idea!! Hahaha no I have to fix this and get it under control....what about the idea of doing dry rock or the reef ready man made rock for my sump?? That will become live eventually right? Or would that be pointless.....I don't want to buy the live rock if it won't make that big of a difference if I could just fix it with what I have now and some water changes and stuff, but if I need to buy something to help me keep my nutrients under control and tank thriving I will do pretty much anything hahahaha
Damon
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Mmnnn.. Me, I would leave the rock alone right now.. Get things stable and then, slowly add more..
You could easily compound the problem adding things that aren't already in the equation..
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Gwitness
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True true.....so then how do I get the nutrients under control when I barely add nutrients to the tank as is....I feed once a day and definitely don't over feed....the annoying part to me is why are they out of whack in the first place?? Nothing crazy happened, I do not over feed at all....I mean what could have happened?? Also should I add bacteria or no?
Randy Holmes-Farley
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FWIW, with respect to nitrate and phosphate, it doesn't matter if a fish or coral eats the food, or not. Nearly all of the N and P in the food ends up as ammonia/nitrate and phosphate being excreted into the water. An adult fish excretes 100% of the N and P it eats, and even juveniles excrete most of it.
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Gwitness
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Wow had no idea.....so really even if you barely feed and it all gets eaten it's still all going to be nitrates/phosphates regardless.....so really to keep a huge fish load you really need to carbon dose or some type of reactor to keep upFWIW, with respect to nitrate and phosphate, it doesn't matter if a fish or coral eats the food, or not. Nearly all of the N and P in the food ends up as ammonia/nitrate and phosphate being excreted into the water. An adult fish excretes 100% of the N and P it eats, and even juveniles excrete most of it.
Damon
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Now that, I admit, I did not know either.. Hmmnnn.. Interesting.. So like he said randy, how do we basically control our deal with it?
From what your saying, and I believe you, starving animals is not only cruel, but pretty futile..
So is there anything that is good for fish that is low on n and p in particular? And maybe even had a low si content?
From what your saying, and I believe you, starving animals is not only cruel, but pretty futile..
So is there anything that is good for fish that is low on n and p in particular? And maybe even had a low si content?
Nearly all of the N and P in the food ends up as ammonia/nitrate and phosphate being excreted into the water. An adult fish excretes 100% of the N and P it eats, and even juveniles excrete most of it.
I believe this was a typo at 100% (bolded). A fish, just like any other living organism, must utilize at least some of the phosphate that it ingests for life sustaining processes. I've read various scientific studies (fresh and saltwater fish) and the amount of P excretion varies widely (generally somewhere around 50 - 90%, depending on species and type of food injested).
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Gwitness
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It won't lower pH or O2 more than NOPOX, except that with more vinegar there will be more pH lowering at the immediate time of addition and less pH lowering later when organisms consume the acetate. If you just add it during the day when pH and O2 are naturally highest, you should be OK.
When dosing nopox I was dosing 12 ml a day.....what do you recommend me for white vinegar a day?
Randy Holmes-Farley
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An adult fish (like an adult human) excretes roughly 100% of the P it ingests, and most of that is as inorganic phosphate, although some is as organic phosphate forms in feces. It does not, and cannot, accumulate long term in nongrowing organisms. Where would it go?
The same is true for N.
You are right that for actively growing fish, they accumulate N and P in their new tissues, and that value is, as you suggest, less than half of what they take in. Often much less than half. To take it all in, they'd need to grow each day roughly similar in volume (and, of course same in dry mass) to the foods you feed. That isn't typically even close to being attained in most settings.
I show that here:
http://www.advancedaquarist.com/2012/3/chemistry
from it:
Impact of Foods on the Aquarium Phosphate Balance
Now we come to the heart of the issue. The actual amount of phosphorus present in foods and what it means. In order to understand the effects of foods, we need to understand what happens to them when added to an aquarium. Some aquarists are under the misconception that eaten foods do not contribute to the free phosphate in the water. Many aquarists are told the mantra of feeding only as much as is eaten, and they confound this idea with the assumption that when doing so, one minimizes the phosphate release. That idea is simply untrue.
A fish or other organism that eats foods takes in substantial phosphate, as shown above. But what happens to it? If the organism is not actually expanding in size (such as an adult green chromis, or a person), the phosphate that is taken in is almost entirely excreted back into the water. The only exception to that process is the very small amount of phosphorus that goes into eggs or sperm, and since in most aquaria those items are rapidly consumed by other organisms, the phosphorus will ultimately get into the water.
Growing organisms do take up a small amount of phosphorus from the diet and retain it in their growing tissues, but the emphasis is on small. A study of a fish farm with rapidly growing rainbow trout in the ocean showed that 78-82% of the phosphorus feed to the fish was lost to the environment. A second aquaculture study using normal fish foods showed that 62% of the fed phosphate was released to the environment, with 35% being released as soluble phosphate available directly to algae, and 27% as phosphorus in fecal pellets (which if not removed, will break down in an aquarium releasing the phosphate again). Another study showed that 81.5% of commercial diet phosphate was released to the environment, but that with a "special" diet with low phosphate and low fish meal this could be reduced to 64% lost. A fourth study showed that growing fish fed slightly less phosphate than they need (to optimize theoretical uptake) take up and retain different phosphate sources differently. Using a purified protein diet, they observed retention of 72% of the phosphorus, 51% retention of phosphorus from added fish bone meal, and higher levels of uptake and retention for inorganic phosphate supplements (such as sodium phosphate).
This sort of study is of concern in aquaculture settings due to environmental contamination due to the released phosphorus and nitrogen. To my knowledge, however, it has never been done in a reef aquarium. Such phosphorus balance studies have also been performed in people for many years. In adults it is clear that nearly all phosphate taken up is excreted, mostly in the urine and some in the feces. Even in young growing children, the amount of phosphorus retained from the diet is only 5-20% of that consumed, with 80-95% excreted in the urine and feces. While such studies are fairly far removed from reef aquaria, they do supporting the idea that organisms take in a lot more phosphorus than they retain, even when growing.
Consequently, reef aquarists should expect that much of the phosphorus added to a reef aquarium in the form of foods ultimately ends up in the water as phosphate. Whether that portion getting into the water is 95% or 35% won't substantially impact the conclusions below that foods add a very large amount of phosphate.
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I'd try 3-4x the volume of NOPOX that you were using in distilled white vinegar as a starting point.
Randy Holmes-Farley
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All nutritious foods must have a lot of N and P. The answer is to increase export if nutrients accumulate.
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Gwitness
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Okay thanks! And you said about the ph and oxygen drop when I dose.....so when I dose it should I divide it into 2 doses a day?? So if I'm dosing 30ml a day just do 15 ml at morning and 15 at night?
