Tropic Marin Plus-NP, why combining N+P+Carbon in the same bottle?

[Randy Holmes-Farley]

Hello,
Since I have developed these products I want to describe the ideas behind the products.

We want to make our products as easy to use and at the same time as safe as possible. The view at nutrients is very much a matter of personal opinion. In my eyes these opinions are not always correct. Acropora species and other SPS have a certain ecological physiology and certain demands in aquaria. Nuisance algae have a bit different demands. We want to offer safe N and P additives for different tanks with different stocks of fish and corals, mainly for use with our balanced calcium additives like Original Balling, Carbo-Calcium and All-For-Reef. These tanks tend to be rather on the low phosphate side.
We are just redoing our product for tanks with calcium reactors which adds only organic nitrogen and no phosphate because the calcium reactor filled with coral rubble usually supplies enough phosphate to the corals.

The nutrients in our N and P additives are a combination of organic and inorganic N and P. These nutrients are combined with an organic carbon additive. This seems contradictory at first glance but in my opinion it is not. With these products we want to introduce a dynamic equilibrium of nutrients. Let me explain this by the image of a bucket with an own faucet under a water faucet. If you open only the water faucet the bucket will be full somewhen and flow over. If you close the water faucet completely and open the bucket faucet it will run dry somewhen. In a dynamic equilibrium both faucets are opened to a certain degree. By mechanisms like increasing water pressure with rising water level in the bucket this increases the likelihood of a balanced flow of water through the bucket without running dry completely and without flowing over a lot. With some likelihood the water level in the bucket will stabilize at a certain level although water is added continuously. Small regulations of the water faucet or of the bucket faucet will result in only minor variations of the water level. This is the explanation of a dynamic equilibrium we want to create for nutrients.

The organic carbon source in my opinion has a second very positive effect. If you add inorganic ortho-phosphate to a tank low in phosphate, at first much of the phosphate is adsorbed to rocks, sand and gravel, all the calcareous materials in the tank. Only after these calcareous materials have reached a certain degree of saturation enough phosphate remains in the water to be tested and to nourish corals. The phosphate concentration suddenly jumps up although you have changed nothing with your phosphate additions. You stop phosphate addition, phosphate concentration decreases in the water but the phosphate adsorbed to calcareous materials remain in place. Nuisance algae and cyanobacteria start to grow at the expense of the adsorbed phosphate while the corals have no access to the adsorbed phosphate. These phosphate swings are amongst the worst things that can happen to your corals and to your tank because SPS are quite sensitive to phosphate swings. This has something to do with their rapid calcification which needs and consumes phosphate.

The role of the organic carbon source is to increase the growth of heterotrophic bacteria on the corals, the decoration and in the water and increase the incorporation of phosphate into bacterial biomass. Corals have direct access to the bacterial biomass growing on their surface and in their gastric cavity, and to bacterioplankton forming in the water. Much of the bacterial biomass growing on other surfaces will be eaten by grazers or forming secondary bacterioplankton by sloughing off. Both processes give the corals access to further nutrients. We have tried to find a organic carbon source that is most beneficial to the corals and maybe to the symbiotic bacteria growing on and in corals. In this way we have tried to "target feed" the corals with nutrients instead of saturating rocks and gravel with phosphate for algal growth.

That is a short description of the ideas and experiences behind our nutrient additives and we hope you agree that they work quite well.

Thank you for the clarification.

 

[Big E]

Didn’t you say that it worked for you for 15 months?

No, I said I tested it for 15 months..........I spent months trying different approaches like reducing the dose and also put GFO in short term to re- balance. In the end the results were the same as other carbon dosing regimes.

If you want more in depth info you can pm me.

I would suggest if you want to use it then you're going to have to use all their follow up additives to fix things. Again Red and the other commercial brands have the same follow up products.......they'll call them aminos, elements, ect. I don't know what's in each company's products but they are designed to keep the overall balance.

With homemade products( vodka, vinegar) people end up dosing nitrates, amino acid, or use GFO in combination.

I can run a balanced system with just GFO and a skimmer, so these systems had no advantage for me. I don't like adding products(chemicals, unknown additives) on the tail end of the cycle. Imo, it's much better for the system to process it in the form of fish food, amonium and urea from the fish.

 

[Evaaron]

Anyone know where to get NP-Plus in the US?

 

[LARedstickreefer]

Anyone know where to get NP-Plus in the US?

I got some on eBay. There isn’t anymore though and the seller said 2 months.

 

[Evaaron]

I got some on eBay. There isn’t anymore though and the seller said 2 months.

Bummer, why cant the tropic marin us stores like @Bulk Reef Supply carry this for us?

 

[LadyTang2]

Yes, this describes it quite well.

1. Are we talking about elimi NP or bactobalance here?

2. I thought Elimi NP was basically bactobalance for tanks with carx's, Is that correct?

3. "The combination of phosphates with organic and inorganic nitrogen compounds and an organic carbon source prevents the phosphates from being adsorbed to calcareous materials" - Is it the carbon dosing thats preventing the phos from being adsorbed or is something about the organic vs inorganic sources of phos?

 

[Randy Holmes-Farley]

1. Are we talking about elimi NP or bactobalance here?

2. I thought Elimi NP was basically bactobalance for tanks with carx's, Is that correct?

3. "The combination of phosphates with organic and inorganic nitrogen compounds and an organic carbon source prevents the phosphates from being adsorbed to calcareous materials" - Is it the carbon dosing thats preventing the phos from being adsorbed or is something about the organic vs inorganic sources of phos?

I won’t justify the claim, but many forms of organic P won’t bind to calcium carbonate. That said, it isn’t a problem that inorganic phosphate does that I can see. No inorganic N binds to calcium carbonate.

 

[droog]

No, I said I tested it for 15 months..........I spent months trying different approaches like reducing the dose and also put GFO in short term to re- balance. In the end the results were the same as other carbon dosing regimes.

Very interesting thread. My experience is the same as Big E. I used RS Nopox for about 18 months on my 130g mixed reef. Nitrates were controlled to <0.5ppm but PO4 would rise over time, and I would suffer from problem algae growth.

It became difficult to buy the RS product where I lived, so I made my own carbon source based on a forum recipe of approx. 80:20 vinegar:vodka. This was cheaper, seemed to work the same way. I read as much as I could on the topic. Talk about "Redfield Ratio" led me to believe that carbon dosing might be a "balanced" solution by itself. In my case this didn't seem to be the case. Maybe it depends on many different factors, corals, feeding habits etc. A carbon source that includes No3 may help export additional po4 but its difficult to see how a manufacturer could determine the amount suitable for everyone.

While carbon dosing I had to run GFO in a reactor to keep No3/Po4 levels balanced. I only needed a small amount of GFO but it's another variable to worry about. Having said that, small amounts of GFO maybe helpful - usually its binding PO4 but when water levels get too low, GFO can leach PO4 back out to the water. I assume this "equilibrium" could be helpful but my understanding of the chemistry may be too limited.

Anyway, it would be nice to have a filtration/export mechanism that is balanced with respect to N03 & PO4. I'm now trying to grow Chaeto macroalgae in a sump refugium rather than carbon dosing.

-droog

 

[Hans-Werner]

it would be nice to have a filtration/export mechanism that is balanced with respect to N03 & PO4.

I think in this general way it is not possible. It depends on several factors determining your N-P-balance.

If you run a coral rubble reactor this will act as a continuous supply of phosphate and result in a surplus and buildup of phosphate in the tank.

If you add calcium and alkalinity in chemically pure forms like Balling or other balanced calcium additives the phosphate consumption by calcifying organisms like coralline algae and corals will most likely predominate over the phosphate supply. In this case it is more likely to get a phosphate deficit.

Different organic carbon sources may, depending form bacterial biofilms and suitable places, lead to different amounts of dissimilatory nitrate reduction (nitrate reduction to N2 and other N-gasses) and also influence nitrate-phosphate-balance.

So it is impossible to make a product or find a supply for all situations. Our Tropic Marin products are designed for chemically pure calcium additives.

 

[Randy Holmes-Farley]

Talk about "Redfield Ratio" led me to believe that carbon dosing might be a "balanced" solution by itself. In my case this didn't seem to be the case.

Organic carbon dosing is not typically balanced at all. There can be much more nitrate reduction because organics drive denitrification, which consumes nitrate and little to no phosphate.

Consumption of nitrate and phosphate by macroalgae and other photosynthetic organisms is closer to balanced, although that doesn't, IMO, make it inherently more desirable.

 

[droog]

I think in this general way it is not possible. It depends on several factors determining your N-P-balance.

Thank you Hans-Werner for posting. Indeed, if it were easy everyone would have a solution already.

Organic carbon dosing is not typically balanced at all. There can be much more nitrate reduction because organics drive denitrification, which consumes nitrate and little to no phosphate.

And thanks Randy. This feels like quite a provocative statement "little to no phosphate". I think there should be some reduction in phosphate e.g. to make the cells of the bacteria or something no? (I'm sure this is a massive oversimplification - I'd be interested to learn more if its understandable to a general science audience). My experience was that certainly very skewed to nitrate export. Some hobbyists dose nitrate in an effort to boost phosphate export; I chose to use GFO.

Consumption of nitrate and phosphate by macroalgae and other photosynthetic organisms is closer to balanced, although that doesn't, IMO, make it inherently more desirable.

Why not? I think it does make it inherently more desirable.

-droog

 

[Hans-Werner]

I think there should be some reduction in phosphate e.g. to make the cells of the bacteria or something no?

Yes, I agree, bacterial growth consumes phosphates, and, under certain circumstances, like oxygen swings, that may also occur with organic carbon dosing, bacteria may even store polyphosphates over their actual demand.

What can hardly be predicted is the share between bacterial growth and denitrification. It depends a lot on circumstances.

 

[Randy Holmes-Farley]

And thanks Randy. This feels like quite a provocative statement "little to no phosphate". I think there should be some reduction in phosphate e.g. to make the cells of the bacteria or something no? (I'm sure this is a massive oversimplification - I'd be interested to learn more if its understandable to a general science audience). My experience was that certainly very skewed to nitrate export. Some hobbyists dose nitrate in an effort to boost phosphate export; I chose to use GFO.

Denitrification as a process consumes nitrate and uses no phosphate at all. If the bacteria are actively growing, then yes, they will use some phosphate, hence the "little" part of the statement. It is far, far less phosphate per nitrate consumed than aerobic bacteria, algae, or corals will use.

This is a typical chemical representation of the denitrification process that gives the bacteria energy, and the nitrate is not, in this process, used to make any tissue:

organic + 124 NO3– + 124 H+ → 122 CO2 + 70 N2 + 208 H2O

 

[Hans-Werner]

In coral reefs and reef aquaria some contrasting bacterial processes may take place.

I think denitrification mainly takes place when organic carbon supply is high and oxygen supply is low. This typically may occur in reactors with readily degradable material like ethanol and low flow or internal circulation. When oxygen supply is low bacteria use NO3 for breathing, more specifically the O from NO3.

In aerobic environments for sure there is some bacterial growth on dosed organic carbon, otherwise bacterial blooms would not occur. This growth takes place like in most other heterotrophic organism: They take up ethanol, vinegar, sugar or some other organic carbon and part they respire to CO2 to fulfill their energy demand and part they incorporate for growth. For growth heterotrophic bacteria not only need organic carbon but also N to form for example amino acids and phosphate to form for example nucleic acids. In this process N and P are removed from the water and may be skimmed with bacterial biomass.

There are also other processes contributing to the nutrient balance like nitrogen fixation by diazotrophs. In this process with dissolved gaseous N2 ammonia is formed by bacteria and archaea. It is the opposite process to denitrification. Since this process also requires energy, either as light in cyanobacteria or as dissolved organic carbon in heterotrophic diazotrophic bacteria and archaea in theory organic carbon dosing could even fuel nitrogen fixation.

Since contributions of the diverse processes to nutrient balance are largely unknown and may vary we depend on trials and experimentation to find out what works four our tanks and what doesn't. At the moment there is no way to get to conclusive and working results through theory.

 

[droog]

Denitrification as a process consumes nitrate and uses no phosphate at all. If the bacteria are actively growing, then yes, they will use some phosphate, hence the "little" part of the statement. It is far, far less phosphate per nitrate consumed than aerobic bacteria, algae, or corals will use.

This is a typical chemical representation of the denitrification process that gives the bacteria energy, and the nitrate is not, in this process, used to make any tissue:

organic + 124 NO3– + 124 H+ → 122 CO2 + 70 N2 + 208 H2O

Thanks... this makes sense now - great simplification for me

You didn't comment on the second question though: why don't you consider a macroalgae based export that is "closer to balanced" inherently more desirable? I would think the opposite is true, other things being equal (cost, convenience, etc).

-droog

 

[Randy Holmes-Farley]

Thanks... this makes sense now - great simplification for me

You didn't comment on the second question though: why don't you consider a macroalgae based export that is "closer to balanced" inherently more desirable? I would think the opposite is true, other things being equal (cost, convenience, etc).

-droog

Because you have other processes that you may not be able to control that also are not balanced. Phosphate binding to rock and sand and other calcium carbonate surfaces is one balanced toward phosphate. Denitrification is one balanced toward nitrate removal. Foods may be imbalanced, especially if there are bones in them.

Thus, many people get to their target on one (N or P) and have too much or too little of the other.

 

[droog]

I see, thanks!

-droog

 

[Etern1ty]

Hi, I have a 10 months old reefer170 with nitrates between 10-20 (salifert) and would like to get them below 10, currently dosing 0.5ml per day, water volume is around 150liters. Should I up the dose? If yes by how much? thanks

 

[Randy Holmes-Farley]

Hi, I have a 10 months old reefer170 with nitrates between 10-20 (salifert) and would like to get them below 10, currently dosing 0.5ml per day, water volume is around 150liters. Should I up the dose? If yes by how much? thanks

0.5 mL per day dose of what?

 

[Etern1ty]

0.5 mL per day dose of what?

oh sorry, I thought this topic was about NP bacto balance. 0.5ml of NP BB, so I am thinking to maybe try to increase the dose every two weeks or so? Also I have 2 liters of siporax in my sump and I am adding 1/3 of a spoon of ReefActif once a week.