Zero nitrate, 0.2 phosphate

[chimbo84]

I have a one year old 120gal tank with a 40g sump. It’s been looking pretty good for the last couple months despite a small chrysophyte outbreak in the last couple weeks. I’m not super worried about that. The potential issue is my nutrient levels.

I just tested at 0.0 NO3 and 0.2 PO4. I don’t have an algae issue that I’m concerned about but my corals (particularly my torches) have seemed to be a little stressed lately. Polyp extension is not great, the growth has been slow, and the chrysophytes have come back a little.

This tank has always seemed to be nitrate bound. Is this something I should actually try to fix? Every time I try to manipulate my nutrient levels, I get some sort of pest. I’ve had it all - dinos, chrysophytes, cyano, GHA, etc. The tank is finally, after a year long ugly phase, starting to stabilize so I hesitate to do anything and looking for some ideas and feedback.

 

[Stephen Glover]

Corals need some nitrate to survive. There are many ways to raise them from reducing nutrient export to dosing them. Whatever you decide to do take it slow.

 

[MrGisonni]

I got a terrible case of dinos when my Nitrates bottomed out in my 30 mixed reef. I was chasing low nitrates and used Brightwell NO3 cubes in a jar in the sump and they stripped them all in short order. I dosed brightwell NO3 and got them back up. They stayed in the 20s for a while and all was well, but since the addition of a Sunburst Anthias and feeding PE mysis they rose to the 40s. At this point I think I am going to add the cubes again and dose nitrate as needed to hit and maintain within that sweet spot for my reef which is the mid 20s.

 

[jda]

Do you have sand and rock? At a year, they could have anaerobic areas that are turning the no3 into nitrogen gas and completing the nitrogen cycle.

Corals need nitrogen, not nitrate. Most corals cannot use nitrate and some that can have to spend an enormous amount of energy to convert it back to a usable form in the range of 30-70%. If you are feeding your fish well, then there is not much chance that they are nitrogen limited and I would leave it alone.

If you want to help corals, then a usable form like ammonia is better than just adding nitrate on the back end - if you do this, then it was the ammonia that helped and not the back end nitrate number rising. If you want to raise nitrate for dinos, then it doesn't matter and just dosing nitrate is fine - ammonia can do this too, and get some nitrogen to the corals.

I cannot think of a single reason to dose a form of nitrate over ammonia.

 

[chimbo84]

Do you have sand and rock? At a year, they could have anaerobic areas that are turning the no3 into nitrogen gas and completing the nitrogen cycle.

Corals need nitrogen, not nitrate. Most corals cannot use nitrate and some that can have to spend an enormous amount of energy to convert it back to a usable form in the range of 30-70%. If you are feeding your fish well, then there is not much chance that they are nitrogen limited and I would leave it alone.

If you want to help corals, then a usable form like ammonia is better than just adding nitrate on the back end - if you do this, then it was the ammonia that helped and not the back end nitrate number rising. If you want to raise nitrate for dinos, then it doesn't matter and just dosing nitrate is fine - ammonia can do this too, and get some nitrogen to the corals.

I cannot think of a single reason to dose a form of nitrate over ammonia.

Thank you for the detailed response. Yes, I do have sand (60lb) and rock (~100lb). It’s not a deep sand bed but I also have an 2” oolite bottom in my refugium where I run a small ball of chaeto. I also run AFR with Kalk and have seen numerous reports that AFR can have a slight carbon dosing effect.

Based on your build thread, you’ve obviously had amazing success in your reefing “career”. Have you ever dosed ammonia in this manner? It seems very counterintuitive to me to do so. If my coral growth and color wasn’t starting to decline, I wouldn’t even consider a change but I am starting to worry that the long term health of my tank is at risk

 

[Uncle99]

The nitrate test result of 0 seems weird to me with .2ppm phosphate.
Are you confident in your test kit?
Actual zero nitrate is very very hard to reach.

 

[chimbo84]

The nitrate test result of 0 seems weird to me with .2ppm phosphate.
Are you confident in your test kit?
Actual zero nitrate is very very hard to reach.

I tested with the HR Hannah checker. I can check again to confirm but I’m confident in my methodology.

 

[Uncle99]

I tested with the HR Hannah checker. I can check again to confirm but I’m confident in my methodology.

I use this checker as well.
Just interesting that your filter can remove 100% of nitrates in the the waters.
Id get a second check and if low (or none) I use Brightwell Neophos to bump my levels from time to time.

 

[EeyoreIsMySpiritAnimal]

Thank you for the detailed response. Yes, I do have sand (60lb) and rock (~100lb). It’s not a deep sand bed but I also have an 2” oolite bottom in my refugium where I run a small ball of chaeto. I also run AFR with Kalk and have seen numerous reports that AFR can have a slight carbon dosing effect.

Based on your build thread, you’ve obviously had amazing success in your reefing “career”. Have you ever dosed ammonia in this manner? It seems very counterintuitive to me to do so. If my coral growth and color wasn’t starting to decline, I wouldn’t even consider a change but I am starting to worry that the long term health of my tank is at risk

Dosing ammonia is common among coral farmers. As @jda mentioned, for corals ammonia is a more useable form of nitrogen.

 

[Pod_01]

I use this checker as well.
Just interesting that your filter can remove 100% of nitrates in the the waters.
Id get a second check and if low (or none) I use Brightwell Neophos to bump my levels from time to time.

Perhaps not that uncommon, here are my results:

Results from lab:

I do dose amino.
For reference for filter I only use skimmer and activated carbon.
But I am not looking to change anything corals look happy.

 

[Uncle99]

Once in a while, I get a zero result from both nitrate and phosphate Hanna checkers which I know is not true.
As long as you believe your result is accurate, not hard to bump.

 

[Lebowski_]

Dosing ammonia is common among coral farmers. As @jda mentioned, for corals ammonia is a more useable form of nitrogen.

That's interesting. I guess not an option for those of us with fish or inverts. Ammonia was the big baddy in this hobby for a long time but I am learning there is a different relationship when it's just coral.

 

[EeyoreIsMySpiritAnimal]

That's interesting. I guess not an option for those of us with fish or inverts. Ammonia was the big baddy in this hobby for a long time but I am learning there is a different relationship when it's just coral.

Yes, it IS an option for those with fish and inverts... I think you misunderstood what others have said.

 

[EeyoreIsMySpiritAnimal]

Yes, it IS an option for those with fish and inverts... I think you misunderstood what others have said.

Remember, a tank is considered cycled (aka, has a sufficient amount of nitrifying bacteria for the bioload) when it can process 2ppm ammonia in 24 hours. Adding small amounts of ammonia rather than nitrate - when the goal is feeding coral- is FINE.

 

[jda]

It is important to point out that nitrate is not the same thing as nitrogen... and phosphate is not the same thing as phosphorous. I tried to be clear about what I typed since they are not synonyms. Nitrogen and phosphorous are building blocks of life. Nitrate and phosphate are waste products in our tanks.

There is a long thread in the chemistry section that talks about nitrate. Is is a good read. In the end, there are two things in the thread that are important 1). the only thing in a tank that NEEDS nitrate is anaerobic bacteria, and 2). having some nitrate might mean that you have enough nitrogen in other forms, but if you don't have any nitrate you still could have plenty of nitrogen (see #1). Everything besides anaerobic bacteria certainly can, and likely prefers, to get their nitrogen from other things. Not all corals can use nitrate to get nitrogen. but those that can expend a lot of energy in the 30-70% range (nobody knows for sure). What most people think that nitrate is doing is not correct and has been just parroted incorrectly on the internet for a long time. Ammonia/ammonium is the best source of nitrogen for most things. Your fish make it constantly. You can supplement if you want - I use janitorial strength ammonium from ACE hardware. Small doses of ammonia are fine and will quickly be consumed by corals, algae, bacteria, etc.

A tank should not be considered fully cycled until it can turn nitrate into nitrogen gas. This is a common thing in nature and will happen in many tanks that have sand and effective live rock where those anaerobic bacteria can develop to do their job. It is no issues to have no3 near zero as long as nitrogen is available in other forms.

I know that people are scared of ammoni[a,um], but they should not be. Heck, nitrate and phosphate in elevated numbers are just as dangerous, but for other reasons.

As for phosphates, all that we can test for is orthophosphate... a very simple form of phosphorous. It appears to be the least likely form of phosphorous that stuff likes to use and is the final step in breakdown. Most of the things in our tanks seem to prefer to get phosphorous from either organic material (like bacteria and other microscopic things caught in their slime coats) and from metaphosphate which are complex bindings of phosphorous with many other things attached. You cannot test for either one of these. You fish produce metaphosphate which the corals seem to prefer and also the microscopic things in your tanks can use to multiply. What is left over is orthophosphate, which people test for which appears to mostly be not useful. Having some po4 show up on a test kit probably means that you have enough other types of available phosphorous in the tank, but there is no need to let them rise.

Phosphates can bind to rock and sand. This is where most of them go in tanks. The rock and sand will bind to "equilibrium" with the water in an exponential way - the more phosphates that you add, the more will bind. When you remove phosphate from the water, some will unbind from the rock and sand. This can be good in tanks like mine where the po4 is 1-3 PPB on Hannah - it acts as a buffer to make sure that it never gets to zero. In tanks where there is lots of phosphate in the water, there is a massive amount bound in the rocks and sand and it acts like a reservoir.

This is different than getting building blocks to corals., but when dealing with some pests like dinos, having no3 and po4 rise can help, but not in the way that most think. The rising levels of no3 and po4 growth limit dinos and make their cellular processes not work as well and the die back. You are not growing things to outcompete them with no3 and po4 since as we detailed above, the things that could outcompete them do not likely use those things.

 

[FrugalReefer]

Increasing my bioload by adding more fish and turning off my skimmer for part of each day helped to increase my barely detectable nitrates.

 

[biom]

Based on your build thread, you’ve obviously had amazing success in your reefing “career”. Have you ever dosed ammonia in this manner? It seems very counterintuitive to me to do so. If my coral growth and color wasn’t starting to decline, I wouldn’t even consider a change but I am starting to worry that the long term health of my tank is at risk

Don't do anything that makes you uncomfortable or sounds counterintuitive to you. Intuition is sometimes most valuable approach in this hobby with so many uncertainties.

I cannot think of a single reason to dose a form of nitrate over ammonia.

There is no doubt that ammonia is preferred as nitrogen source by corals and many others. But there are reasons why one could chose dosing nitrate over ammonia/um:
1. Because they don't feel comfortable to dose ammonia/um. If you were told for 20 years that ammonia is bad and you've experienced fish deaths because of incomplete nitrogen cycle then it will be very hard to be convinced to do so.
2. Ammonia is more toxic for fish and corals than nitrate is and in case of overdosing could cause tank crash
3. There is no much information how to dose ammonium safely and how to control it. For ex, you are starting with 2 ppm ammonium daily and it disappear in 24 hours, so you are continuing dosing three days - 6ppm in total, all of it disappear and you decide to check nitrates and OMG it shows 20+ppm Nitrate, (because 6 ppm NH4 will be oxidized to 20+ ppm NO3). Even worse you are testing nitrate with Salifert test and it shows 100+ ppm Nitrate. It is because Nitrite that is formed in ammonium oxidation interfere most hobby Nitrate test and give false high readings, but you are not aware of that and get panicked, start big WC, adding additional filtration media and things are going from bad to worse...

That is said IMO ammonium dossing is more for advanced reefers and coral farmers. For the average reefers if they want to increase nitrogen in their aquariums I think the best advise is:
1. Slowly Increase fish bioload if possible
2. Slowly decrease filtration: reduce skimming, remove socks, remove media, remove rocks
3. And if none of above-mentioned is helping/possible then dose Nitrate.

 

[jda]

Maybe we could help people understand and quell their fears? There are many more dangerous and difficult things in this hobby that people are comfortable with like using extreme acids, kalkwasser, etc.

I have janitorial strength ammonium from the hardware store and when I get low on fish in a system, I just add a ML a day, or so. It never is detectable and appears to do the job. I have no idea how many ppm this adds, but it is a 70 gallon system and I could probably do the math if I wanted to, but it likely nowhere near 2.0 ppm.

I have no desire to decrease skimming since I need the gas exchange with my Calcium Reactors and I also want the skimmer to remove any harsh metals bound to organics - I recommend this for nearly nobody. I would also never remove rock since it does so many other good things like house microfauna that could each ich/disease tomonts and give hiding places.

My personality is to never avoid what is best because it is hard or you have to learn. I know that this is not for everybody, but maybe we could brainstorm on how to help those that would like dose ammonium since it is preferred.

 

[Randy Holmes-Farley]

I agree that folks can certainly do ammonia dosing safely. IMO, the questions are:

1. One wants to dose slowly, and to have confidence a doser does not overdose. Once a day manual dosing may be enough, but not always.

2. IMO, there no clear evidence that it gives a better outcome than amino acid or nitrate dosing. Just because a coral will take up more ammonia than nitrate when both are available doesn't mean ammonia dosing gives a better outcome. I take up more ice cream than kale when both are presented. lol

 

[jda]

We don't have any clear evidence that amino acid of nitrate dosing is effective either. Most of the people who do it have something like 2 ppm of no3 and think that they are ULNS and starving their corals (or something measurable) and want to get to 10 or 20. Like having more of an excess is better than having less of an excess.

Kale is a good false equivalency since it is a waste product too. I like it.