Baffled by Nutrient Level Requirements

[ReefGeezer]

I see gorgeous tanks all the time that are reported to have nitrate levels in the 20+ ppm range and phosphate levels of .1 ppm or even much greater. Many or their owners subscribe to the theory that maintaining low nutrient levels is less important than the hobby believes and point to their tanks as proof. I just can't understand why some tanks with similar levels of nutrients get overrun with algae & bacterial outbreaks, while others flourish.

I still struggle with sporadic and varying algae/bacterial issues. I get spots of Cyano, patches of hair algae, and some sort of light tan fuzzy stuff that is hard to scrub off, even though I control nitrate & phosphate to lower but detectable levels. The algae comes and goes and doesn't get out of hand, but I can't get rid of it completely. So, I have some questions and would be interested hearing from those who have it figured.

What limits or controls the algae/bacteria in the higher nutrient tanks that don't have problems? Am I missing some secret formula for balancing nutrient levels and other parameters in the system? Do those with higher nutrient systems simply accept and manage the resulting algae in favor of having better growth & color in their corals? Is there some "hobby level" reading that might explain it in a way I can understand?

 

[SPR1968]

This is a very good question, and I don’t know there is an easy answer or magic formula other than strict control of parameters

I think when tanks are new, and maybe less than a year old, they go through all sorts of ugly stages As the tank matures everything balances out in its own little ecosystem and in particular at a bacterial level.

Also bear in mind most of the tanks you refer to are also run in a controlled manor by their owners. I have nitrates around 10-15ppm and low phosphate at 0.03ppm and my system is now 2 1/2 years old. These parameters are kept by my intervention with various methods hopefully with a view to preventing algae or any other type of outbreak The parameters are stable and strictly controlled

I could easily increase the nitrate to over 20 without any issues, and in my personal experience the best single thing I ever did was to lock phosphate down with GFO to around 0.03ppm so very low.

Hopefully we will get some more answers on this.

And welcome to R2R as well by the way!

 

[EmdeReef]

Welcome to R2R!

IME when starting a new tank you’re better off with lower nutrients. That seems to become less relevant as the tank matures, but I’ve had much better luck with low nutrients and sps frags for example. LPS and softies will prefer higher nutrients overall. I never chase a particular nitrate or phosphate number - usually best to observe your corals and if unhappy try to figure out why before making slow adjustments. test kits are not that accurate esp.for nitrates, just aim for a lower range initially.

New tanks go through all sorts of ugly phases and excess nutrients generally won’t help.

In mature tanks, corals can outcompete algae for nutrients but usually that means well established colonies.

All that said, I’m sure there are many reefers on here who have been successful not caring about nutrients even when starting a new tank.

 

[WVNed]

There are lot of very strong opinions by knowledgeable people here. But many of them are diametrically opposed.
It seems logical if two people are doing exactly the opposite and getting the same result there are other factors in play we don't understand yet.

I have one of the tanks you are talking about. High nitrates and I am dosing phosphates and using Nopox. There must be other factors that control algae/ bacterial growth beyond what we test for in the water.
When you read any of the longer tank problem threads you find that there is no constant pattern to tank parameters for those having the problem. There is also no consistent solution that always works.
Or it could be a lot of people are mistaken about what there tank parameters actually are or are just telling us what they think we want to hear.
In my case I changed lights after a few months. Black boxes to a Photon V2. I went from having algae to having no algae. To my eye the light looks the same.

I also think flow is way more important that we realize. The main difference between a ditch with lots of brown green goo growing in it and a reef is how much and how fast the water flows through them.

 

[Scorpius]

Mature systems 2+ yrs old can handle higher nutrient loads and not suffer major issues. New tanks not so much.

Gotta remember mature systems have the biology that new systems do not.

 

[Foothill Corals]

If this is a new tank just wait it out, if not... Crank up the flow in the tank and get a Tang.

 

[ReefGeezer]

Thanks everyone. To further the discussion...

I dose vinegar @ about 28 ml/day in my 90. The high bioload is pretty high & I feed moderate to slightly heavy... I think. I also dose potassium nitrate every couple of weeks so that the carbon dosing process can help with phosphate. Nitrates in my system are anywhere from 0 to maybe 2.5 ppm right after dosing (Salifert so it's hard to tell) and Phosphates are .02 to about .07 (Hanna 736). My old but reliable skimmer works well and is the only permanent filtration in the system. I have a single reactor and run GAC every once in a while just to polish the water or GFO if algae seems to be increasing. I have lots of flow: An older MP40 and two RW4's. The MP40 runs 40 to 100% depending on my mood. The RW4's run constant @ 100% to keep them from stalling (They are old and suck). Lighting is two Rapid LED Onyx fixtures that run @ 100% for 11 hours a day. I started the tank with about 70 lbs of dry Fiji rock after treating it with Lanthanum Chloride. Tank temp is 79-82 F. The tank is a year old this month. I have one husbandry issue... I do sporadic water changes & might average maybe 20-25% a month.

 

[ReefGeezer]

Mature systems 2+ yrs old can handle higher nutrient loads and not suffer major issues. New tanks not so much.

Gotta remember mature systems have the biology that new systems do not.

I understand that mature systems process nutrients better... big corals colonies, sponges, pods, and all that. But if free nutrients are still high, I'm wondering how the biology in mature systems keeps algae from using them?

 

[saltyfilmfolks]

Hopefully this helps.
A lot of serious heavyweights in these
https://www.reef2reef.com/threads/sps-high-nutrients-myth.283442/#post-3449471

https://www.reef2reef.com/threads/my-home-tank.296635/#post-3626579

Blows most people’s minds really.

 

[Gregg @ ADP]

The key feature: stability over time

My perspectives are different than many simply because my sample size is so large. I’ve pretty much seen every permutation conceivable in reef tanks, and I’ve seen examples of each that was wildly successful, and examples of each that just couldn’t get or stay off the ground.

There are some rules we should follow. There are requirements by these animals that we need to accomodate. But I think that most of those have a fairly broad range and can be somewhat flexible.

And then there’s the adaptation side. Coral has been around longer that just about any animal on Earth. They’ve seen it all countless times over the eons, and they’re still here. That only happens by being able to adapt in changing conditions.

There is a fair amount of research that suggests on the genetic end, there is a high amount of variability even within a species within a community. It shows up all the time in studies on bleaching events, where certain individuals within a population of a species of Acropora, for instance, have a greater tolerance for warmer water than others within the community and are less likely to expel zooxanthellae.

I believe that variation plays a role in why some tanks do well despite less than perfect conditions while others fall to pieces if somebody sneezes near the tank. A little bit of genetic luck of the draw, perhaps.

 

[Flippers4pups]

Hopefully this helps.
A lot of serious heavyweights in these
https://www.reef2reef.com/threads/sps-high-nutrients-myth.283442/#post-3449471

https://www.reef2reef.com/threads/my-home-tank.296635/#post-3626579

Blows most people’s minds really.

The one thing I have learned about nutrients and their levels from my personal experience is when I had phosphates higher than nitrates, that's when I had issues with pest algae. Keeping nitrate higher than phosphate seems to keep nuisance algaes more controlled. On the other hand, when I had nitrate and little to no phosphate, my corals paled considerably. Adding phosphate corrected the color issues.

 

[saltyfilmfolks]

The one thing I have learned about nutrients and their levels from my personal experience is when I had phosphates higher than nitrates, that's when I had issues with pest algae. Keeping nitrate higher than phosphate seems to keep nuisance algaes more controlled. On the other hand, when I had nitrate and little to no phosphate, my corals paled considerably. Adding phosphate corrected the color issues.

You’ll be interested in the high nutrient thread. It’s a long read but worth it.
They don’t seem to care for the most part. Amongst the heavy weight sps growers, I have never heard them mention ratios or balances.
Most organisms use nitrates more than phosphates, the availability of witch in the tank shouldn’t matter , according to them, save in extremes.
Ie , low no3 and high Po4 shouldn’t matter as the organisms still uptake the same amount as if it was high no3 and low Po4.

 

[hart24601]

Grazers and available surface area seem to be a large difference to me. Large tanks that support many fish and inverts that eat every speck of algae along with large coral colonies that take up a lot of the rock (or other growth like sponges) which leave less surface for algae to attach, and with all those herbivores those spots get grazed on. My tank isn’t really big enough for any fish grazers!


It also gets tough to compare how a tank runs with coral colonies that are 2ft wide and has been running for a decade vs a tank with frags that is a year old. It’s easy to see a massive tank with coral bigger than your head and think “I need to match that” but really you might only want to match it when you have coral the size of your head. Many times we don’t know what the parameters were when the tank had frags, if it ever did, or started with colonies.

 

[ReefGeezer]

Grazers and available surface area seem to be a large difference to me. Large tanks that support many fish and inverts that eat every speck of algae along with large coral colonies that take up a lot of the rock (or other growth like sponges) which leave less surface for algae to attach, and with all those herbivores those spots get grazed on. My tank isn’t really big enough for any fish grazers!


It also gets tough to compare how a tank runs with coral colonies that are 2ft wide and has been running for a decade vs a tank with frags that is a year old. It’s easy to see a massive tank with coral bigger than your head and think “I need to match that” but really you might only want to match it when you have coral the size of your head. Many times we don’t know what the parameters were when the tank had frags, if it ever did, or started with colonies.

I like the low available surface area idea. It a least suggests a reason why pest algae might not gain a foothold even when free nutrients are available that should otherwise let them grow out of control. I have a Kole Tang, a Yellow Tang, Turbo & other snails, Hermit Crabs, and one well fed huge Urchin but the algae still survives enough to look bad in spots. I have a lot of exposed rock & not a lot of Coralline. I suppose if there was less surface area, the grazers could probably handle it.

 

[jda]

Consumers are one of the key differences. Algae grows in the wild and even in tanks with low building blocks - I have .1 N and .01P and I can grow bubble and hair algae if I don't have foxface and emerald crabs. If N and P get too high, then they will inhibit photosynthesis and algae can quit growing this way.

When you see tanks with REALLY high building block levels, pay close attention... most of them did not get that way being like that and did most of their building and growing at lower levels. Not all, though. Some will tell you about species and types of coral that they have lost since letting the levels get higher... but the owners do not care and can live with the bunch that is left over. Everybody loves to talk about the Richard Ross tank, but his tank was different when it had lower building block levels... with different corals and stuff. While either can be fun and fulfilling, you cannot do the same things with higher N and P that you can do with lower... and vice versa. The slower growth can be welcome once a tank is full. The nuance matters here, so pay attention.

Generally speaking, once you have enough N and P, then you have enough... 1 N and .01P is not growth limiting and the coral can function the same as if you have 10 and .1. Even slightly elevated N and P can inhibit calcification, which is why you see some keep them low (with high throughput) to get their corals (and coralline) to grow faster. High but not too high, can brown out corals with more zoox... or sometimes make their colors deeper and darker - some love this and some hate it... to each their own. Too high can inhibit photosynthesis, which does not always kill coral, but can slow down the growth.

Low N and higher P seems to be best for corals and keeping algae at bay, but can have some cyano issues... just anecdotes, but also very common where anoxic bacteria in the rock/sand can turn most of the NO3 into N gas, but there is no direct consumer for all of the phosphate.

 

[ca1ore]

It’s an interesting question. Mine is a large, mature system. 700 plus gallons across multiple, interconnected tanks. Nutrients certainly not what I’d consider low - nitrates nominally at 20, phosphates at almost 0.2. I have absolutely no algae issues in the main 450 display, nor in the 120 refugium ..... but loads of it in the 60 frag tank. Why is that, what’s different?

Easy to start with what’s the same. Identical water chemistry obviously, and I have endeavored to match lighting as much as possible. Similar flow levels and temperatures. What’s different? Both display and refugium have most surfaces covered with corals or desirable algae’s. Frag tank has a lot of uncovered egg crate. But perhaps the biggest difference is that I have an army of herbivores in the main display and a highly motivated black tang in the refugium.

I am taking steps to moderate the nutrient levels, though with over 120 fish that’s problematic. It’s been my long held view that low nutrients is just part of preventing algae; the other is to have adequate herbivores. Also remember that absent herbivores even natural reefs can get choked with algae.

 

[cracker]

My75 is over 3 years ols & ate up with constant HA & a few other undesirable stuff. I'm at my wits end at this point .Iv'e tried nutrient control . water always tests zeo I dose up a little & the HA just goes crazy with growth . I've stopped dosing at this point until I can come up with another way to go . It's very frustrating.

 

[ReefGeezer]

Thanks everyone. I've read & watched the referenced media and thought a lot about your responses. I'm a little less confused now, but give me time, I'll get even even more confused in short order! I've been signed up on this site for quite a while but, as you can see, haven't participated much. I plan on changing that. I appreciate the tone of the discussion, and the information and advice given. Thanks again.

 

[ReefGeezer]

My75 is over 3 years ols & ate up with constant HA & a few other undesirable stuff. I'm at my wits end at this point .Iv'e tried nutrient control . water always tests zeo I dose up a little & the HA just goes crazy with growth . I've stopped dosing at this point until I can come up with another way to go . It's very frustrating.

I've been lucky enough to not get bad outbreaks. Just stuff that looks bad here & there. I feel for you though. I hate algae! I don't know what I would do if it got bad in my tank.

 

[EmdeReef]

Thanks everyone. I've read & watched the referenced media and thought a lot about your responses. I'm a little less confused now, but give me time, I'll get even even more confused in short order! I've been signed up on this site for quite a while but, as you can see, haven't participated much. I plan on changing that. I appreciate the tone of the discussion, and the information and advice given. Thanks again.

BRS also did a video on this (apologies if already posted): https://www.bulkreefsupply.com/vide...althy-reef-tank-the-brs-wwc-system-ep9-brstv/

As you can see from responses here there's no settled yes or no answer. Too many variables, different experiences and there is no right or wrong answer.
Unlike temperature and some other metrics we don't really know what's considered high or low for corals as it's not a well studied field.

At risk of irritating some people, I don't think it's fair to call it a myth that for sps optimal environmental conditions appear to be lower nutrients. At least that's the case in their natural habitat. Heavily nutrient polluted areas of the ocean seem to favor only a handful of species and there are observed issues in skeletal structures etc.

Even though our tanks are nothing like the ocean we do try to replicate conditions as best we can.