Are elevated nutrients a problem, or not?

[Randy Holmes-Farley]

Thanks for the input so far, folks. Very interesting discussion.

 

[Cichlid Dad]

I think an interesting slat to your question would be those that reply high, or low, or who cares should post images of their display. Sort of puts it into perspective.

New setup, nitrate high phos .1. lots of clean up crew . So far algae under control, some of the uglies start to show, but go away soon after. The acro in the tank were browned out and are now coloring up. I stopped worrying about low levels and started keeping them a little bit higher. I'm seeing great growth especially on my Monti's. I'm still very new to all of this, but this is my best tank yet.

 

[drolmaeye]

Following this thread, as my first tank just stabilized . . .

Nitrate is a solid 9-11, not too clean, not too dirty, nice job by me.

Phosphate is a solid 0.35 - 0.45, at 10x the recommended value, my reefing career could end at any time.

 

[Alpha_and_Gec]

this is a thing that I had been thinking of since I started to pay attention to my tank again, because my mother wanted lots of corals but I came back to a massive concentration of nitrates. In my opinion, a safe nutrient level is all about control. Can you keep your nutrients at the same level without regular spiking? Can you regularly change water? Does your ecosystem contribute significantly to nutrient control? What does the tank itself do when you aren't actively trying to reduce/increase nutrients? I had purged all of my nutrients at the start, because it was at a level I could not control with corals, macros and small - scale water changes. Now however, I am open to nutrient intake, knowing that my coral and filtration can eat a small ammonia spike in a single night and that there's going to be a lot more corals coming in this week and the next, as well as now that I can change water at the maximum scale, I can make massive cuts to the nutrient economy at a moment's notice.

Nutrients... is nutrients, after all. Things need it to live, so it of course is a necessary component of a healthy reef, but if your food reserves are constantly going empty or if new nutrients are constantly entering the tank, there may be a problem.
Also... Nitrates are definitely not as bad as everyone make it out to be in my experience, but high levels of nitrates can be a bit difficult to control.

 

[jda]

I imagine that we are talking about elevated residual nutrients specifically in the form of po4 and no3? My general opinions is that the levels matter, but they might not matter to you.

I mostly keep acropora and clams, so my experience is limited. I also keep some nice mushrooms and Colorado Sunbursts in these same systems and they don't seem to care about much.

There are some acropora that will start to suffer with po4 and .1 and no3 and 5. Some will die if you double this. Some do not mind or care at all. You CANNOT lump all corals in together with these kinds of discussions.

If you want to be able to keep any acropora at any time, you are going to need to have lower po4 and no3 levels. If you want to let the levels rise, then some things might STN or RTN, but others will be fine.

There is zen is just keeping what your tank can support and not trying to worry about numbers too much.

All of this said, nothing will suffer at near-seawater residual no3 and po4 levels if they are provided with other forms of N and P. I run 1-3 ppb of po4 and just a trace of no3 and this will grow anything quite well. My tank happens to most do this on it's own and I might not work any harder if they raised up a bit.

 

[Subsea]

@jda
kudoes to your above post. There is much wisdom in zen.

“There is zen is just keeping what your tank can support and not trying to worry about numbers too much.”

When I first started Reefing 53 years ago, there was no internet and no reef club. At this same time, I worked on a 28 day on 28 day off work schedule in deepwater drilling. I started off with softies and after 50 years live stock choices include GSP, Xenia with an assortment of non-photosynthetic filter feeders including flame scallops & sea apples.

With that said, I choose to run high nutrient systems, that recycle nutrients into the microbial loop to feed hungry mouths.

 

[jda]

For example, I keep OG PM and real ORA Pearlberry and I rarely see them thrive in tanks where the no3 and po4 get too high... they can take a little, but I would be shocked if they can handle a 1.0 po4 and 100 no3 tank. ...so if you want to keep these, then keep the levels lower... if not then just get another purple coral and have some zen moments. Please don't think that since you see a few acropora in a high residual nutrient tank that any of them can make it... or if your coral grows a bit in a higher residual nutrient tank that it will not grow faster in a lower one. There is a difference, but it might not matter to you.

A big litmus for me is ORA German Blue Digi. I like this coral. The polyps shine blue with lower no3 and po4. When the blue starts to dull, the no3 and po4 are getting higher. It still has blue polyps, but they are not as bright and iridescent. This is hard to explain to some since people can get mad since they are seeing blue in their higher no3 and po4 tanks and take exception, but they likely have not seen what the coral can be for comparison. ...and this is a digi.

I like to keep some of these types of corals. My tank also handles lower no3 and po4 quite well the way that I set it up, so this works for me.

Lastly, I was talking to a guy at MACNA that does AQ and they choose corals to grow on plugs in the ocean that will work well with higher no3 and po4 and also lower-output heavy-blue lighting. Many of the corals in the hobby today have survived and are good choices for these types of tanks.

 

[alindell]

When I added the brightwell neo phos and neo nitrate. I instantly noticed the coral colors pop and become darker and healthier. Before I had no detectable phos or nitrate. Corals looked light in color. Still alivea but I could tell some were barely hanging in there. I truly believe it comes down to stability in the other parameters and being in acceptable stable ranges of nutrients with good import and export from the system. Reefs like lots of nutrients, but they don't like dirty water if that makes sense.

Think about this; the water in the natural reefs are filled with a near infinite amount of organic material and nutrients, but yet nitrate and phosphate are basically undetectable. The ocean has the benefit of being so massive and filled with life that the reefs have a constant supply of nutrients, but not to the extent where the water becomes polluted or dirty. In our tanks with modern filtration we filter out every fricken thing in the tank and so when we test nitrate and phosphate it can read 0. The water looks good, but there is nothing for the corals to eat and so they get weak (faded colors, pastel). A little deviation in lighting or other parameters and boom the more susceptible species die. Point being have good filtration and export, but keep a healthy nutrient load with coral food, fish, biodiversity, adding nitrate or phos if you need it. I add oyster feast, amino, reef roids every now and then. Remember I dont want to make the tank toxic, but I want enough to provide enough nutrients for the corals to feed. Alot of them with absorb it in the water column without actually seeing them eat the solid food products.

I think my system consumes nutrients pretty fast for some reason. Growth doesn't really have seemed to have slowed when I added phos and nitrate directly to the tank. The biggest thing I did for growth was add kalk to get ph up and start manually dosing alk and cal as the corals are starting to consume so much of the stuff. I also add in all for reef for supplementing the alk and cal, but also for other elements in the tank that can be depleted. Monthly water change helps add in some other elements too and allows me to suck out and clean off some of the rocks that fill with detritus.

 

[MnFish1]

Yes! This is very important, I think. I have not just that one, but six total (sailfin, powder brown, gem, achilles, yellow, white tail bristle tooth) and a foxface. They are constantly cleaning up the rocks. I only keep a couple snails, as the tangs do such a good job of keeping it clean. This is in a 320, so please don't come at me tang police haha.

In my experience, you get algae either way (as @Randy Holmes-Farley noted in point 2), so having a good cleanup crew is extremely important.

IMHO - with a 'tang tank' - it may be that instead of eating the algae they are eating the food they are given. IMHO - many people feed their fish too often and too much (not you hunterallen)

 

[MnFish1]

Thanks for the input so far, folks. Very interesting discussion.

99.99 percent of the people posting are waiting for your opinion

 

[Superd513]

Elevated nutrients are one of the most talked about issues in reefkeeping, with folks on all sides of the issue.

There is, however, no simple answer to the title question (IMO).

I thought I'd start a thread for a wide ranging discussion of this issue, and to gather many of the bits of data and anecdotes and comments in one place.

I'll start off with a few ideas to provide some background and ideas to debate.

1. It is clear that there are great reef tanks that most hobbyists admire with nutrients (nitrate and phosphate, particularly) ranging from low levels (say, less than 2 ppm nitrate and 0.01 ppm phosphate) up to quite high levels (>1 ppm phosphate and >100 ppm nitrate).

2. It is clear that there are reef tanks overrun with bryopsis, valonia, green hair algae, caulerpa, dinos, cyano, or other problems at nearly any of the values mentioned in 1.

3. Scientific studies on the effects of elevated nutrients on growth of hard corals are mixed. In some studies they thrive. In some studies they do not. In some studies, some growth forms (e.g., encrusting) are decreased and others (e.g., linear growth) of the same coral are increased. In most study cases, these are not getting the natural particulate foods they would get in the wild, and how much of what particulate foods they get in aquaria likely varies greatly based on husbandry techniques used.

4. Scientific studies on elevated nutrients in the ocean often suggest that hard corals decline and other organisms take over. This result is, of course, not due to solely to effects of nutrients on corals, but to effects on competing organisms as well.

Since a reef aquarium is, in some ways, a small microcosm of the real ocean, I think point 4 should not be dismissed, even knowing that point 1 is valid.

Perhaps point 1 is only valid for elevated nutrients if there are other aspects of the aquarium that allow hard corals to thrive. For example, herbivores to control algae.

Here, for example, is a recent analysis relating to hard corals in the ocean with elevated nutrients:

A new perspective of nutrient management of subtropical coastal stress-tolerant scleractinian coral communities

A new perspective of nutrient management of subtropical coastal stress-tolerant scleractinian coral communities

Elevated nutrients decrease the healthy status of coral communities, which can be stressful on reef corals, always resulting in decreased live sclerac…

www.sciencedirect.com

from it:

Elevated nutrients decrease the healthy status of coral communities, which can be stressful on reef corals, always resulting in decreased live scleractinian coral cover (LSCC).

When my tank levels were high, by that i mean nitrate at 25 ppm and phosphate at .9 ppm my corals seemed to be ok. My BTA looked very happy. Once I started carbon dosing that's when everything looked amazing . My zoas exploded and grew like crazy. Now i have the levels low I've cut back on the dosing and everything looks hungry. My BTA is always fully open but his tentacles are short and its mouth is always open. I have a 29 gal nano mostly lps. I do biweekly water changes. I feed the corals reef roids once a week and my BTA twice a week with Mysis. the clowns once a day.

 

[Randy Holmes-Farley]

99.99 percent of the people posting are waiting for your opinion

I don’t have any special answer, just some thoughts.

We keep hundreds, if not thousands of different organisms in reef tanks.

We also have many creatures that grow so well that we call them pests (e.g., aiptasia).

A reef tank is a pretty unnatural environment, no matter how hard we try to mimic the ocean.

We know almost nothing about the true optimal conditions for each species we keep, whether a desired inhabitant or a pest. The ocean may not be optimal at all.

Put some subset of these organisms into a given reef tank with its own peculiar conditions, and I think we are left not knowing what conditions will make it appear to thrive to our liking.

That why I think lots of different conditions may work fine while similar conditions may not work out in a different tank.

For that reason, mimicking some of the aspects of a very successful tank may fail if you neglect a critical aspect of the mimicking, and it may be an aspect you never considered.

 

[Superlightman]

For me, it seems that until 0,2 phosphate everything is ok, but over that some sps most of times tenuis and milleporas get stn or brownish, but some sps doesn't seem to have problem even with 0,4 or higher. I think it depends on the species

 

[Koty]

I don’t have any special answer, just some thoughts.

We keep hundreds, if not thousands of different organisms in reef tanks.

We also have many creatures that grow so well that we call them pests (e.g., aiptasia).

A reef tank is a pretty unnatural environment, no matter how hard we try to mimic the ocean.

We know almost nothing about the true optimal conditions for each species we keep, whether a desired inhabitant or a pest. The ocean may not be optimal at all.

Put some subset of these organisms into a given reef tank with its own peculiar conditions, and I think we are left not knowing what conditions will make it appear to thrive to our liking.

That why I think lots of different conditions may work fine while similar conditions may not work out in a different tank.

For that reason, mimicking some of the aspects of a very successful tank may fail if you neglect a critical aspect of the mimicking, and it may be an aspect you never considered.

In other words: a reef tank is a (very) complex system.
All things considered, IMO, the principal goal is to try and get our tank as close to natural seawater as possible. As you said, it is probably not ideal for many tank inhabitants, but it's a safe average that most of them can adapt to. With all respect to the profound arguments about Nitrate and phosphate, the best concentration, ratio, etc., the general rule is to try and minimize them. This is because regardless of how essential they are, they roughly indicate how dirty our waters are. Each tank can be viewed as a complex system with multiple variables. One key variable to consider is derived from the age of the tank or its "biological succession stage." To this end, IMHO, we should follow the parameters as our tank reaches some form of maturation (In my case, it was about two years ± 3 months). A general indication is the hobbyist becoming a useless LFS customer because the tank inhabitants, critters, corals, and fish do not die anymore but rather thrive and grow. We should use every possible export system: carbon dosing, skimmers, refuge, reactors, and carbon, OK...WCs too, and at the same time, let our tank stabilize its own parameters.

 

[chipchipbro]

Well..
I used to keep my PO4 at 0.07-0.12 and NO3 around 8-12 - I got some really nice colors with that numbers on my Acros.

Now I was on vacation and when I returned I saw some of my acros are looking dry, washed out and grey and have a bit less PE (not all, just a few). Then I tested and sawthat po4 is 0.01 and no3 1

I am not sure if this color change comes from low nutrients... I a, dosing po4 and no3 now.. but somehow my tank consumes alot more then before.. I can dose 0.03 po3 and a few hours later my level is again 0.01

For me the best colors where achieved around 0.05-0.1 po4 and 5-10 no3

 

[jda]

I have not ever kept a coral that did not grow faster or look better with no3 and po4 levels more towards ocean levels. This includes Colorado Sunburst Anenomes which grow very quickly for me - like can divide ever 3 months.

However, I always have an abundance of nitrogen and phosphorous from fish waste.

I think that too many people overlook avaiable forms of N and P and only look at the waste products since they have test kids for no3 and po4. Often, when no3 and po4 rise, or stay high, it was the feeding that got them there that mattered, not the actual no3 and po4 numbers. The same is likely true when they decline... not enough food to keep the no3 and po4 higher. Remember that if no3 registers then you need just an excess and a tiny bit can be excess.

I just came back from a week moving an offspring to college. I have dual auto feeders on my acropora tank since Ehiem only feeds 4x per day. ...so 8x pellets when I am out of town. I feed more frozen when I am in town.

Heavy import, heavy throughput and heavy export seems to work the best for any coral, for me. ...so lots of nitrogen and phosphorous, but low levels of no3 and po4.

Nitrogen, phosphorous and light with wider spectrum and more output is what people should be going after, IMO.

I REALLY wish that we would break these type of discussions down into available nutrients vs residual nutrients.

 

[jda]

BTW - some corals have distinct advantages in our tanks, but most only think about potential negatives. I do not have parrotfish, starfish, etc. that crunch through acropora or eat their tissue - no predators. No hurricanes or tropical storms. Consistent lighting. Hopefully no pollution.

I do think that taking the best of the wild and making it more consistent is a good place to start. Then, tweak if you need to.

 

[Spare time]

BTW - some corals have distinct advantages in our tanks, but most only think about potential negatives. I do not have parrotfish, starfish, etc. that crunch through acropora or eat their tissue - no predators. No hurricanes or tropical storms. Consistent lighting. Hopefully no pollution.

I do think that taking the best of the wild and making it more consistent is a good place to start. Then, tweak if you need to.

I think what you pointd out is great. The wild is not "ideal" but if we take what the corals like from their environments and put that in a box, the chances of them growing and being healthy goes up.

 

[jda]

I assume that nature is ideal until proven otherwise. I am pretty well convinced that not everything is ideal in nature, but you have to start somewhere, right?

I have acropora that were collected from colonies that are out of the water for 3-5 hours a day. I do not duplicate the sun beating down on them at 2600 PAR when exposed to air, or exposing them to air. I do duplicate the heavy fish load in the area and low residual no3 and po4. I do not duplicate 2600 PAR of sunlight, but I get as close as I can with spectrum from 350 to 850nm and high output up to 1000 PAR sometimes. All of this said, those corals that are exposed to the sun for 3-5 hours a day still grow faster than mine and look better, so who is to say that air exposure is not ideal, right?

I would not just throw away nature and think that us humans are smarter or have stood the test of time better. We might be in some cases and the thought exercise is beneficial, but probably not the majority.

 

[Lavey29]

Just curious what we have determined is High Nutrients? I think we know the low end but I bet everyone's estimate of what is high might be different here and there depending on their own experiences as each tank is unique.

For instance my nitrates dropped to 8 after a water change and for my tank that is low because I like 10 to 15 for mixed reef. For someone else. 8 may be high for their SPS dominant tank. So I guess this is very subjective in the end and based solely on your own tank and the results you get with parameters you try to maintain?

Lots of great responses in the thread and thanks for sharing your knowledge Randy.