Is Carbon, Nitrate, and Phosphate Dosing Bad For the Hobby?

[jda]

I agree, though something as simple as the suggestion of "feed your fish more" can have a pretty dramatically positive effect on a N or P starved system.

I wish that I could edit that to say "dose N and P." I misspoke/typed a bit. I have nearly no issue with feeding more. I don't care for a statement of "dose N and P and feed your corals" with the combination of thinking that 1). building blocks are actual food, 2). that more of a surplus is going to do anything, and 3). doing it by adding N and P on the backend.

Even with feeding more, lighting is still, to me, the largest factor for why corals are pale and don't look great assuming competent level of water parameters... but this is another discussion for another day. Raising N and P when people already have a surplus won't help much except to maybe darken up some colors and make them more monotone. You can get some different colors with more nitrogen and phosphorous, but they usually are not as bright and the contrast is not as good. To each their own on a preference.

Corals are fed by light, through the zoox. Also, if they can catch something. This is the SPS forum and I am Ok with saying as a general rule that nearly nobody is going to be able to feed their SPS with much success... the few exceptions are probably not worth talking about since those coral will thrive without it. This is not the same as other "coral" which can get some benefit. I am sometimes amazed that people focus so much thinking that N and P are food and ignore light as the main energy source for their SPS. More light does indeed add more energy (to a point).

 

[Mortie31]

I agree with you that new tanks should not be dosing N and P, but sadly you lost me when you started with the redfield ratio. (Or triton ratios either) It IMO is something that I wish could be removed from any discussions pertaining to marine aquaria, it is frankly wrong in this situation. Carbon dosing has been used successfully for years by reefers and in fact is a really beneficial additive on so many levels not just for lowering Nitrate levels, but again IMO is shouldn’t been seen as a main method of reducing nitrates.
Some German reefers have been dosing Urea to achieve what you are suggesting with ammonium, if that’s the way you want to go it’s worth googling.
I believe the fad in predominantly the US of dosing N and P is a direct result of the way you cycle and run your tanks, ie dry rock and bacteria, and trying to keep things too clean from day one, a tank needs to mature and gain biodiversity, it isn’t about a quick cycle and fill it full of sticks.

 

[road_runner]

I wish that I could edit that to say "dose N and P." I misspoke/typed a bit. I have nearly no issue with feeding more. I don't care for a statement of "dose N and P and feed your corals" with the combination of thinking that 1). building blocks are actual food, 2). that more of a surplus is going to do anything, and 3). doing it by adding N and P on the backend.

Even with feeding more, lighting is still, to me, the largest factor for why corals are pale and don't look great assuming competent level of water parameters... but this is another discussion for another day. Raising N and P when people already have a surplus won't help much except to maybe darken up some colors and make them more monotone. You can get some different colors with more nitrogen and phosphorous, but they usually are not as bright and the contrast is not as good. To each their own on a preference.

Corals are fed by light, through the zoox. Also, if they can catch something. This is the SPS forum and I am Ok with saying as a general rule that nearly nobody is going to be able to feed their SPS with much success... the few exceptions are probably not worth talking about since those coral will thrive without it. This is not the same as other "coral" which can get some benefit. I am sometimes amazed that people focus so much thinking that N and P are food and ignore light as the main energy source for their SPS. More light does indeed add more energy (to a point).

Well its all connected really, nothing more or less important than the other.
Zooxanthellae do not actually "eat" light..
They use light energy to metabolize carbon nitrogen and phosphorus...hence from scientific stand points the "eating" action is happening on the phosphorus and carbon not the light
Zooxanthellae are embedded in coral tissue, they metabolize carbon and phosphorus, and their waste is amino acids and other elements that feed the actual coral..symbiotic relationship..

 

[Ike]

100%, nothing baffles me more than ti treat this problem "over feed" "turn off skimmer" "overfeed and turn off skimmer" "stop water change"
All these come from poor understanding of a comment someone read somehwere ha ha ha

At one point my dumb self was doing 25% weekly water changes because I could see my tank visibly go downhill if I waited longer. I was convinced I was going too low on some element that water changes was replenishing. I'm pretty convinced it was only helping because it would give the tank a tiny boost in the N and P it was starved of. Keep in mind that the downhill would have probably looked great to most people. But I've grown a lot of Acropora from frag to colony many times over, I know when something isn't quite right just from looking at them. That's not a luxury that people that are newer to the hobby have, they simply don't know the signs until it's often too late.

We want people to thrive in this hobby and have the best chance of success, and I think there needs to be more policing of bad advice on these forums. This is a nice, happy forum, and I like that most of the time. But people need to get a little more hardcore with correcting and pointing out bad and lazy advice!

 

[road_runner]

At one point my dumb self was doing 25% weekly water changes because I could see my tank visibly go downhill if I waited longer. I was convinced I was going too low on some element that water changes was replenishing. I'm pretty convinced it was only helping because it would give the tank a tiny boost in the N and P it was starved of. Keep in mind that the downhill would have probably looked great to most people. But I've grown a lot of Acropora from frag to colony many times over, I know when something isn't quite right just from looking at them. That's not a luxury that people that are newer to the hobby have, they simply don't know the signs until it's often too late.

We want people to thrive in this hobby and have the best chance of success, and I think there needs to be more policing of bad advice on these forums. This is a nice, happy forum, and I like that most of the time. But people need to get a little more hardcore with correcting and pointing out bad and lazy advice!

Could it agree more...amen to that.
I do it often thu I get in troubles ha ha ha

 

[Ike]

I agree with you that new tanks should not be dosing N and P, but sadly you lost me when you started with the redfield ratio. (Or triton ratios either) It IMO is something that I wish could be removed from any discussions pertaining to marine aquaria, it is frankly wrong in this situation. Carbon dosing has been used successfully for years by reefers and in fact is a really beneficial additive on so many levels not just for lowering Nitrate levels, but again IMO is shouldn’t been seen as a main method of reducing nitrates.
Some German reefers have been dosing Urea to achieve what you are suggesting with ammonium, if that’s the way you want to go it’s worth googling.
I believe the fad in predominantly the US of dosing N and P is a direct result of the way you cycle and run your tanks, ie dry rock and bacteria, and trying to keep things too clean from day one, a tank needs to mature and gain biodiversity, it isn’t about a quick cycle and fill it full of sticks.

You make a good point, and I do think that where a lot go wrong is when they're going through some typical algae cycles with newer aquariums that are establishing themselves. I was using urea when I was playing around with N dosing in 2014. I got spooked when P started coming down too rapidly and decided to let things ride.

 

[Ike]

I agree with you that new tanks should not be dosing N and P, but sadly you lost me when you started with the redfield ratio. (Or triton ratios either) It IMO is something that I wish could be removed from any discussions pertaining to marine aquaria, it is frankly wrong in this situation. Carbon dosing has been used successfully for years by reefers and in fact is a really beneficial additive on so many levels not just for lowering Nitrate levels, but again IMO is shouldn’t been seen as a main method of reducing nitrates.
Some German reefers have been dosing Urea to achieve what you are suggesting with ammonium, if that’s the way you want to go it’s worth googling.
I believe the fad in predominantly the US of dosing N and P is a direct result of the way you cycle and run your tanks, ie dry rock and bacteria, and trying to keep things too clean from day one, a tank needs to mature and gain biodiversity, it isn’t about a quick cycle and fill it full of sticks.

Also, I feel the redfield ratio is important as one of many examples that could indicate that it's a rarity for a photosynthetic calcareous coral to be P limited.

Just a couple of comments. Many corals and Tridacna clams consume single-cell algae. See here:

Coral Nutrition, Part Two: Foods for Corals - Reefs.com

Coral Nutrition, Part Two: Foods for Corals - While once reefkeepers believed lighting and chemical additives were all we needed to sustain corals, coral nutrition is now recognized as vital for a thriving captive reef. Dana Riddle delves into more detail about foods for coral.

www.advancedaquarist.com

I culture micro-algae to feet to the new 120-gallon tank and feed as much as 500 milliliters per day. I spot feed two Goniopora corals with microalgae.
I have 25-gallons of green water currently under culture (see photo.) I use Guilliard's f/2 formula to fertilize the algae tanks, and there water has elevated concentrations of phosphorus and nitrate. Naturally, this is added along with the green water. I monitor the algal cultures for N and P using a Hach colorimeter. P = 0.55 ppm and Nitrate as N is 0.6 ppm (under-reported due to the cadmium reduction method I use.) The display tank has only 5 fishes at present (2 ocellaris clowns, 2 Yellow tangs, and 1 Lamarck's angel) but they are heavily fed - at least 2 cubes of mysis, algae cube for tangs/angels, and flake food. Nutrients in the display tank water is nitrate as N (1 ppm or less, and P 0.02 ppm or so.) Protein skimmer is on only at night so microalgae isn't removed during the day. The sump has an overflow full of Chaeto and is lighted only at night. I occasionally add a Fauna Marin Reef BactoBall or two.
At night, the water swarms with zooplankton.
So far so good. Calcareous algae are starting to cover rock and dark plastic areas, filter-feeders (feather dusters) are growing, zooplankton is abundant, and corals are doing well.

I would be so tempted to cut down the skimming on the tank to one day a week to see how it reacted. After it's a little more established of course...

 

[jda]

I'm pretty convinced it was only helping because it would give the tank a tiny boost in the N and P it was starved of.

How did you get N and P in your salt mix? Did you add it? All that I have ever used do not have any in there. Do you use NSW?

People get warning and posts deleted if you correct or point out bad or lazy advice. Some of the time, you cannot even ask for people to demonstrate any kind of experience. I always thought that there should be a forum where anybody can ask a question, but only people who have years of experience with a pile of photos, posts, 2015 TOTM articles, or whathaveyou to otherwise vet somebody as experienced can answer them or give advice.

 

[Ike]

How did you get N and P in your salt mix? Did you add it? All that I have ever used do not have any in there. Do you use NSW?

People get warning and posts deleted if you correct or point out bad or lazy advice. Some of the time, you cannot even ask for people to demonstrate any kind of experience. I always thought that there should be a forum where anybody can ask a question, but only people who have years of experience with a pile of photos, posts, 2015 TOTM articles, or whathaveyou to otherwise vet somebody as experienced can answer them or give advice.

I just assumed that brown film on my IO bucket was organic matter There has to be traces of N and P in most freshly mixed saltwater. I'd say it's also quite possible that the water change appeared to be benefiting by stunting the growth of corals temporarily and therefore lessening the need for nitrogen and phosphorus. After not doing a single water change in 4 years and having thriving Acropora is suggestive that at least in my system,lack of trace and minor elements is not a limiting factor in growth.

 

[Dana Riddle]

Very nice, Dana! I often forget about how phytoplankton could be beneficial and contribute to N and P availability at various stages in the food chain and I probably disregard it too often because it doesn't directly benefit most of the corals I keep. So many cool types of tanks to keep, so little time!

I have however had some pretty incredible success with various species of Goniopora, growing several from small frags to huge colonies and a few from small wild colonies to large colonies. I attribute at least part of my success to having very little mechanical filtration and feeding heavy with dried foods.

There have been at least two papers written on feeding Goniopora - one was by Fabricius (which was later partially retracted.) The other was by Peach, and I have been unable to find it. In any case, it is most interesting to hear your observations! I didn't mention it, but I also dose an amino acid supplement, Reef Roids, the Fauna Marin coral food, in addition to the microalgae. I can't say for certain which is responsible for happy Goniopora, but the LFS says they think it is the microalgae that they feed the tank twice a week so I took their recommendation. I have noticed a drastic increase in zooplankton since feeding the tank microalgae.

 

[Dana Riddle]

I just assumed that brown film on my IO bucket was organic matter There has to be traces of N and P in most freshly mixed saltwater. I'd say it's also quite possible that the water change appeared to be benefiting by stunting the growth of corals temporarily and therefore lessening the need for nitrogen and phosphorus. After not doing a single water change in 4 years and having thriving Acropora is suggestive that at least in my system,lack of trace and minor elements is not a limiting factor in growth.

Craig Bingman stated IO has measurable ammonia in it when freshly mixed. I checked, and of course, Craig was right.

 

[Ike]

There have been at least two papers written on feeding Goniopora - one was by Fabricius (which was later partially retracted.) The other was by Peach, and I have been unable to find it. In any case, it is most interesting to hear your observations! I didn't mention it, but I also dose an amino acid supplement, Reef Roids, the Fauna Marin coral food, in addition to the microalgae. I can't say for certain which is responsible for happy Goniopora, but the LFS says they think it is the microalgae that they feed the tank twice a week so I took their recommendation. I have noticed a drastic increase in zooplankton since feeding the tank microalgae.

You can see two of my big colonies from my old display here... One was a 1" frag grown to be basketball sized when it was open and softball size when closed. There were two others large colonies of other species in the display and four additional species in the system before my move. I don't know how much it helps, but the only feeding they got (at least in my head) was me mushing up flake food between my thumb and index finger every feeding. Oh, and I feed heavy, it looks like a formula 1 flake food blizzard in my tank when I feed.

Reefkeeping Magazine - April 2015 Tank of the Month

Reefkeeping ...an online magazine for the marine aquarist.

reefkeeping.com

 

[Ike]

Craig Bingman stated IO has measurable ammonia in it when freshly mixed. I checked, and of course, Craig was right.

That makes sense considering what I was observing. I wonder what the amount of ammonia is per 100 gallons. Hmmmm...

 

[Ike]

You can see two of my big colonies from my old display here... One was a 1" frag grown to be basketball sized when it was open and softball size when closed. There were two others large colonies of other species in the display and four additional species in the system before my move. I don't know how much it helps, but the only feeding they got (at least in my head) was me mushing up flake food between my thumb and index finger every feeding. Oh, and I feed heavy, it looks like a formula 1 flake food blizzard in my tank when I feed.

Reefkeeping Magazine - April 2015 Tank of the Month

Reefkeeping ...an online magazine for the marine aquarist.

reefkeeping.com

Thought I could link to specific photos, but guess not. They either didn't highlight the goniopora in the sytem very well, or I didn't send the good Goniopora shots, but if you search the bottom of the tank you can see a few decent pics .

 

[Mortie31]

An old paper, I’m sure most of you have read it, however it postulates that there is a narrow margin of error for overdosing DOC that could directly kill corals, by causing to much of an increase of bacteria within the coral. As part of N-DOC testing triton measure organic and inorganic carbon, which could potentially give us an indication if we’re getting close to these levels of 2-10ppm as suggested by Rohwer

Feature Article: Total Organic Carbon (TOC) and the Reef Aquarium: an Initial Survey, Part I

Department of Chemistry, The Pennsylvania State University, University Park, PA 16802. Ken and Kelly report on their work on Total Organic Carbon and how it relates to the reef aquarium.

www.advancedaquarist.com

 

[Mortie31]

Also, I feel the redfield ratio is important as one of many examples that could indicate that it's a rarity for a photosynthetic calcareous coral to be P limited.

Sorry I don’t understand, how can a ratio of C,N and P in phytoplankton be useful to a calcareous coral or show it can/cannot be P limited?

 

[Dana Riddle]

An old paper, I’m sure most of you have read it, however it postulates that there is a narrow margin of error for overdosing DOC that could directly kill corals, by causing to much of an increase of bacteria within the coral. As part of N-DOC testing triton measure organic and inorganic carbon, which could potentially give us an indication if we’re getting close to these levels of 2-10ppm as suggested by Rohwer

Feature Article: Total Organic Carbon (TOC) and the Reef Aquarium: an Initial Survey, Part I

Department of Chemistry, The Pennsylvania State University, University Park, PA 16802. Ken and Kelly report on their work on Total Organic Carbon and how it relates to the reef aquarium.

www.advancedaquarist.com

I guess having high DOC in an aquarium is possible, but I've performed the Five-day Biochemical Oxygen Demand test a number of times. These were performed in accordance with EPA-approved methods (incubation in darkness for 120 hours at 20C, and used either a polarographic or one of the newer luminescent dissolved oxygen probes. These were 'straight' samples with no dilution - a full 30 milliliters was used.) For the test to be valid, there has to be a drop of at least 2 ppm dissolved oxygen but the most I ever saw was 0.2 ppm. These samples were spiked with a chemical that inhibits nitrification, thus they are reported as Carbonaceous Oxygen Demand. I wasn't dosing any carbon source (methanol, vodka, carbon-based additive, etc.) so it is possible that some aquaria have high levels of organic carbon, I just haven't personally seen one.

 

[Dana Riddle]

You can see two of my big colonies from my old display here... One was a 1" frag grown to be basketball sized when it was open and softball size when closed. There were two others large colonies of other species in the display and four additional species in the system before my move. I don't know how much it helps, but the only feeding they got (at least in my head) was me mushing up flake food between my thumb and index finger every feeding. Oh, and I feed heavy, it looks like a formula 1 flake food blizzard in my tank when I feed.

Reefkeeping Magazine - April 2015 Tank of the Month

Reefkeeping ...an online magazine for the marine aquarist.

reefkeeping.com

Beautiful tank! Congratulations!

 

[Dana Riddle]

Too hot to do much outside... Here's a photo of one of the thousands of 'bugs' in my tank. I saw an increase of these after I started dosing microalgae (along with the nitrate/P content of the culture water.) These bugs could be responsible for feeding the corals and not the microalgae.

 

[bar|none]

Thx for this thread. I was just starting to toy with n and p dosing but did not understand it. Will now proceed or not with more caution.