Why no nitrates!!!

[Mark75]

Tank is 3 years old and grows coralline okay,...nothing crazy like I have seen with my metal halide and T5 tanks.

My lighting is a Hydra 52(non-HD) running 8 hours 25 white/100 blues/15 red/7 green.

test results as of last night;
cal.-410
alk.-7.7
nitrates-0
phosphates-.09

 

[jda]

Do you have any of those halides or T5s still that you can put on there for a while to eliminate a variable?

I am not a LED user for acropora, so this is not worth anything... but I would get the white, red and green a bit higher... full spectrum is better to color corals and then you switch to whatever you want to illuminate them (most people like bluer illumination). I have never really seen a fantastic acropora tank under Hydras (although I am sure that they probably exist), but the best Radion tanks that I have seen have all channels at 100% and the lights way up high.

 

[jda]

Maybe I should keep my alk around 6dkh? Doesn't low alk cause slow growth?

Sorry that I missed this. Alk at 6 is fine. 7 is fine too. ...just keep it rock solid at these levels. Natural sea water is around 7 with some lower in lagoons and stuff. Alk at 9 is kinda high for a SPS tank. I like to keep mine between about 6.5 and 7.2, depending on my CaRx tune... any higher and I can get some STN with my NSW level building blocks - the tissue cannot grow as fast as the coral can calcify and this is why tips burn or leading encrusting edges start to die back.

 

[Scorpius]

Acropora heavy tanks t5/mh. Leave the led Acropora tanks for the experts.

 

[Jeff_H]

Following along... This is an interesting thread for me since I have a similar issue with very low nitrates. While I don't have a silver bullet for @Mark75, there are a couple of comments I would like to add to help others who find this thread.

@jda appears to be a very knowledgeable and seasoned reefer so I don't want to contradict what he has posted, but I do want to offer a point of view from someone with less skill. In principle, I agree with his comment that anything above true zero is enough NO3 but I feel the closer you are to either edge (high or low), the greater a chance you have that something will get out of balance. Targeting a middle number (3-5 ppm) will give you a deeper buffer and a better chance of surviving fluctuations if/when they occur, especially for newer reefer like me and many others on R2R.

I believe this now because I successfully ran my mixed tank at 1 ppm for over two years with no issues. About three months ago, I donated a very large and messy eating cowfish to a public aquarium. I cut my feed down, added 11 smaller fish (18 total), and my nitrates still dropped under the detectable level of my Nyos test kit. I increased my feeding 2-3 times a day, but could not get my levels back up. Common advice I hear from experienced reefer all the time is not to chase numbers so I didn't focus on it. That turned out to be a big mistake since I believe it opened the door for the Dino bloom I'm now dealing with. So I would say for 'newer reefer', 3-5 ppm might be a better target to provide a buffer for mistakes and drifts as livestock or equipment is added or removed. Two of the main resources I found that have me thinking this way is the moderator's suggestion on the R2R Dino thread with over 5,600 posts. They now believe keeping your NO3 and PO4 levels elevated will help stop and prevent Dinos and other issues. Also, the BRS WWC Video series also has a dedicated video on the topic which suggests the same targeted levels.

I would also apply the 'middle ground' number to Alk as well. Running a tank below NSW is running on the edge and might turn out to be a mistake given how fast alkalinity can change if you're not constantly monitoring it. The key phrase in @jda last post is "rock solid" if you can't do this and are not monitoring Alk on a very frequent schedule, you likely will not have the same results. This is why Triton Method recommends 8 dKH and not 7 dKH. That said - I do believe ULNS will have bleaching issues with Alk levels above NSM, so I would correct the nutrient issue first and raise the Alk levels slowly later if you want to get your values at a higher 'safer' range.

For my issue... I'm running the full Triton Method so I don't have filter socks and very few water changes so there was nothing to change there to improve my situation. I started to reduce the photoperiod on my refugium slowly over the past month from 14 hours to now six hours. I've been testing No3 and Po4 levels ever 2-3 days to see if there are any changes. I have seen an increase in algae in the tank, plus better colors in the corals, but as of this past Saturday, I still have zero and zero. I'm hopeful I will get some reading soon so I don't have to dose N03 or PO4. BTW: I also shut off my skimmer for a week, about a month ago and saw no improvement in levels. I turned it back on after the PH started dropping, but I tuned it to skim very dry. I am interested on one of the earlier comments that if you do dose, it is not a permanent thing. I will need to look into this more to see if others have had the same results.

@Mark75 - Good luck with your system!

 

[jda]

I agree with not getting to close to zero. However, the method is usually the problem and zero nitrate is the symptom. I use an established sand and rock bed to manage mine - it would take days to weeks or even months for this population to change with an increase or decrease in nitrate... so not much risk here in anything happening fast. With other methods, like carbon dosing, it can go bad very quickly. As a rule of thumb, the natural methods can keep you low, but really never get you too low. If you want to control this yourself with media and chemicals, then just know that you are probably not as good as the nature that evolved for this specific purpose and you really have to keep an eye on it.

I think a lot of people are focused on their "current level" too much and not enough on the method. I know that methods oft take a lot of patience and some people are not flush with this.

 

[Jeff_H]

I agree with not getting to close to zero. However, the method is usually the problem and zero nitrate is the symptom. I use an established sand and rock bed to manage mine - it would take days to weeks or even months for this population to change with an increase or decrease in nitrate... so not much risk here in anything happening fast. With other methods, like carbon dosing, it can go bad very quickly. As a rule of thumb, the natural methods can keep you low, but really never get you too low. If you want to control this yourself with media and chemicals, then just know that you are probably not as good as the nature that evolved for this specific purpose and you really have to keep an eye on it.

I think a lot of people are focused on their "current level" too much and not enough on the method. I know that methods oft take a lot of patience and some people are not flush with this.

I agree... I tried carbon dosing when I first set up the tank, and while it worked, I could not easily maintain it without constant testing and adjustment. I travel often for work so I've been looking for more natural and stable ways to let the system balance itself without relying on technology. I'm just finding the refugium to be way more efficient than I expected given my current bioload. If I can't get reading on my next test, I plan to raise my H380 light to reduce the PAR and see if that helps. Unfortunately, this light is not dimmable so I'm limited on what I can adjust.

 

[Neo Jeo]

 

[Radman73]

Fighting the same issue. Zero nitrates. I've had detectable nitrates just once in the year and couple of months that the tank has been set up and that was ~6 months ago. I've tried increasing my feeding without any real luck and now have what appear to be Dino's. I may also cut my fuge lighting period down and see if that helps but I've had little to no cheato growth in the last few months either. Corals have largely stopped growing and I lost a couple of can frags. One is holding on with a single, small polyp. Otherwise nothing is awful with the tank, and the Dino's don't seem overwhelming yet. Honestly considering a run to Lowes to pick up some stump remover and dose to 2-3pm and see what happens .

@Mark75 You are not alone lol!

As an FYI:

Tank is 220gal
Sump is 40gal
Fuge is 75 gal.
PO4 is .02-.04 per Hanna.

 

[jda]

If you are going to dose nitrate, then get some more pure sodium or potassium nitrate from Amazon. People have reported issues stump remover - not all, but enough to worry about it.

 

[Mark75]

First of all ,thanks to everyone who has/is contributing, this thread seems to address a problem effecting more than just myself.

I am not interested in dosing nitrates for several reasons, one being I have tried it and found it created worse problems, not that dosing is wrong just not what I would like to do. I put a lot of faith(maybe to much) in nature finding its own equilibrium and I am lazy and don't want two more parameters to test, nitrates and phosphates. If you dose nitrates you better test phosphates and often!

It is so perplexing how many reefers struggle with high nitrate and others have to dose it.

My plan is to remove my filter sock/ feed even more(if I can keep my phosphates in check)/turn my skimmer WAY down/and add some fish(5-6 Anthias should do the trick) until then I am letting my alk slowly drop to 6dkh. If that doesn't raise nitrates I am breaking out my trickle filter and bio-balls!!!

 

[Radman73]

First of all ,thanks to everyone who has/is contributing, this thread seems to address a problem effecting more than just myself.

I am not interested in dosing nitrates for several reasons, one being I have tried it and found it created worse problems, not that dosing is wrong just not what I would like to do. I put a lot of faith(maybe to much) in nature finding its own equilibrium and I am lazy and don't want two more parameters to test, nitrates and phosphates. If you dose nitrates you better test phosphates and often!

It is so perplexing how many reefers struggle with high nitrate and others have to dose it.

My plan is to remove my filter sock/ feed even more(if I can keep my phosphates in check)/turn my skimmer WAY down/and add some fish(5-6 Anthias should do the trick) until then I am letting my alk slowly drop to 6dkh. If that doesn't raise nitrates I am breaking out my trickle filter and bio-balls!!!

It is ironic how some of us need to add nitrate while so many fight to shed it. Not thrilled about dosing nitrate either, but I'm at least a month away from adding 4-5 more fish to the tank, assuming they all survive QT. PO4 is where it should be for me, so feeding more will mess that up. Awkward position to be in I guess. My goal is simply to get nitrate to register so 1-3ppm. I'll dose to that and watch for effects. Easy enough to stop and let the tank drop it to 0 if need be.

 

[Shinte122305]

I’ve had this issue before. I kept feeding and feeding and nada.I fixed this issue by dosing nitrates from brightswell I buy it off amazon. I ended up needing to dose nitrates every time I fed and eventually my system stabilized and not w I have a reading of 5-10 nitrates every two weeks when I test it. Every now and then I need to dose again to keep it at this level. My tanks 5 years old and the rocks are closer to 10 so my tanks very mature it eats up nitrates and thencorals where starving. Everything looks better after a few weeks of higher nitrates.

 

[Hans-Werner]

Trying to have nitrate is ridiculous. Corals don't need nitrate. Nitrate makes corals dark brown. As long as your corals are not nearly bleached they do not lack nitrogen or show any signs of nitrogen deficiency. Nitrate is the nitrogen compound least preferred and valuable for corals.

 

[Shinte122305]

Trying to have nitrate is ridiculous. Corals don't need nitrate. Nitrate makes corals dark brown. As long as your corals are not nearly bleached they do not lack nitrogen or show any signs of nitrogen deficiency. Nitrate is the nitrogen compound least preferred and valuable for corals.

No offense but your knowledge is a bit outdated, read up on today’s info on nitrates and phosphates. My best friend has one of the most beautiful frag tanks I’ve ever seen with LPS softies and a few sps with 10ppm nitrates and 0.1 phosphates all year round. This photo is with the lights already dim I took it really late, but you can see the colors everything is beautiful and bright nothing is brown or washed off and the corals grow like weeds. This low nutrient thing people went after everyday becomes a thing of the past as we realize now with today’s kits if you read 0 your starving your tank.
Photo was taken with an iPhone so sorry for the washed out blue...

 

[Hans-Werner]

And you are really shure the nitrate is the cause and not 0.1 ppm of phosphate? Did you do controlled experiments? In my experience phosphate is important for good fluorescent colors. Of course bright fluorescent colors look even brighter on a dark brown coral but the nitrate does nothing for the coral. The uptake of the coral for nitrate is much much more than saturated at 5 ppm or even 2 ppm. In most corals uptake should even be more than saturated at 1 ppm. It just can't take up more nitrate than at these concentrations. That is very basic biochemistry.
If I ever will find the time I will upload an image that shows that Stylophora 'Milka' can also look good if it is brightly colored with pink and bluish hues instead of purple on dark Brown.

 

[Da8]

Trying to have nitrate is ridiculous. Corals don't need nitrate. Nitrate makes corals dark brown. As long as your corals are not nearly bleached they do not lack nitrogen or show any signs of nitrogen deficiency. Nitrate is the nitrogen compound least preferred and valuable for corals.

I don't agree either.

Nitrates and phosphate have a very important point in the growth and color of sps. Without them, episodes of STN are a constant when you have good growth rates.

Tank is 3 years old and grows coralline okay,...nothing crazy like I have seen with my metal halide and T5 tanks.

My lighting is a Hydra 52(non-HD) running 8 hours 25 white/100 blues/15 red/7 green.

test results as of last night;
cal.-410
alk.-7.7
nitrates-0
phosphates-.09

I've seen great tanks with your illumination.

Turn on whites!! C'mon!
25? That's part of your growth problems.

Increse it slowly but steady until you see corals react negatively (don't think they will until at least 50%/75%)

About nitrates.

You don't tell us nothing about your feeding routines.

In a mature tank sometimes is very difficult to keep nitrate and phosphates at healthy levels.

Try, as you say, feeding more. Adding few fish, adding aminos.. Etc...

A view of your tank would be great to understand your livestock needs.

By the way. Alk around 7 is great.
Don't worry too much about nitrates if as Hans says, no bleaching or stn is happening.

 

[Hans-Werner]

Nitrates and phosphate have a very important point in the growth and color of sps. Without them, episodes of STN are a constant when you have good growth rates.

This is true for phosphate but not for nitrate. Nitrate is just another nitrogen compound and it is the one least valuable for corals. Besides this the half saturation constants of corals for all kinds of dissolved inorganic and organic nitrogen that come to my mind (nitrate, ammonium, urea, amino acids) are extremely low. You need nearly nothing in concentration of these compounds to fulfil the N needs of corals. Whoever says something else should read about the biochemistry and ecological physiology of Corals, i. e. Sorokin 1995:
The saturation curves of consumption of P04, N03 and
NH4 by corals are similar to the Michaelis-Menten kinetic curve (D'Elia
1978; Webb and Wiebe 1978; Muscatine and D'Elia 1978). This indicates
that the consumption proceeds mainly via the enzymatic active transport
mechanisms. The threshold concentrations at which the consumption starts
are within 0.1-0.2 µmol -l, and that of Vmax 1-2 µmol -l, which is the
same range as in the oceanic phytoplankton. The rate of consumption of
ammonia by corals was twice as much as that of nitrates in their ambient
concentrations (D'Elia and Webb 1977).
.

 

[Da8]

This is true for phosphate but not for nitrate. Nitrate is just another nitrogen compound and it is the one least valuable for corals. Besides this the half saturation constants of corals for all kinds of dissolved inorganic and organic nitrogen that come to my mind (nitrate, ammonium, urea, amino acids) are extremely low. You need nearly nothing in concentration of these compounds to fulfil the N needs of corals. Whoever says something else should read about the biochemistry and ecological physiology of corals.

I'm quite noob at chemistry, so I can't give you any technical and valuable information.
Actually my tank has undetectable N , and 0'08 PO4. But for me is very important to try and rise N levels to 5 to try balance N and PO4 so undesirable cianobacteria or dinoflagelates.

When talking about potassium , I think there is a direct relation between N, PO4 and K. I'm not sure if with undetectable levels of N the relation can be detrimental to this relation, and , as a result, to the colour.

Last, but not least, as I mentioned in the previous post, when having very low nutrient levels, I have risks of STN in my SPS . I cannot use SPS specialised feeding because it usually triggers STN epiodes.

 

[Hans-Werner]

The cited text above says, that with 1 - 2 µmol/l the N uptake is saturated, which means the coral just can't take up more N than at this concentration, further increase doesn´t make any sense. 2 µmol is 36 µg or 0.036 mg of NH4+ or 62 µg or 0.062 mg of Nitrate. Nitrate levels in coral reefs are not much higher than Phosphate levels, in average about 2.5 times higher by weight, this means around 0.04 ppm, and corals show net nitrate uptake.
Everything else you see at higher nitrate concentrations is not a positiv effect of nitrate uptake but rather a sign of stress.