Experiences with nitrate dosing?

[Reefpuck]

Hey everyone. Anyone have experience with raising nitrates/phosphates in their tank? I'm about 6 months into my 90g...and everything is going well. Most of my SPS frags have lightened/lost some color up since I put them in the tank...some more than others. There is growth in most...although not as fast as I think they can grow. 

My main issue I think is nitrates and phosphates are undetectable. I have 7 fish so far...and feed daily/heavily. 

Parameters: Cal 430, Alk 8.0, Mag 1350, Salinity 1.025. Lights are modified LED black boxes.

I have a 55g sump/fuge...with a basketball size of chaeto that I'm slowly trimming down. Do bi-weekly 20g water changes. Run skimmer and 1/2 carbon in a reactor.

Is dosing spectracide stump remover (postassium nitrate) my best option to increase nitrates to around 5ppm? I plan on adding 1 or 2 more fish (tomi tang & watchman goby)...just not sure when yet.

[Gig 'em @ NDstructible]

I either a) feed my fish more or b) dissolve 10 grams of Spectracide into 1 liter of RO/DI water. I then dosed 250 ml into 150 gallons of water to raise by about 5 ppm. Hope that's helpful for you! I find that heavier feeding is the more natural way to raise nutrients

[Isaac]

wait, weed killer as nutrient? weird.  i'd just feed more, keep it more... natural cycle.  nice side effect, you get large happy fish?

[jolt]

I use Seachem Flourish Nitrogen and Birghtwell NeoPhos.  Both are concentrated so a few mL goes a long way.  Just haven't been able to feed my way up to a higher number yet, but I think that's because my tanks are young.

[Merman]

In my experience undetectable nitrates are not good. I had several large colonies start to STN from the bottom up and it took me a while to figure it out. I started (slowly) dosing stump remover and the problem immediately went away and all my colonies started to recover. Also several smaller frags/colonies that were pale looked much more colorful. I’m talking within days.

Keep in mind I have a mature tank and phosphates were normal so I was dealing with an imbalance. Increasing feedings is more of a long term solution so if your situation doesn’t seem urgent that may be the way to go. For me, stump remover worked great because I needed to raise nitrates immediately and not raise phosphates. Increased feedings will raise both.

For what it’s worth I believe the root cause of my undetectable nitrates was my chaeto growing too well over a long period of time. You might also want to consider knocking down you refugium lighting schedule/intensity.


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[Merman]

I'll add that even after correcting the imbalance I still have to dose once a week or so.  I've doubled my feedings and it's still not enough. 

Spectracide is pure potassium nitrate.  Essentially it's just fertilizer.

[FarmerTy]

You can dose the Spectracide but with 5 ppm of nitrates in my system via Spectracide and 5 ppm of nitrates via more fish and feeding, my corals responded better in the second scenario. That being said, in your situation, I'd go ahead and dose the nitrates up to 5 ppm. I'm a believer of low phosphate in SPS tanks like yours. Just better color and better growth IME.

[Reefpuck]

4 hours ago, Gig 'em @ NDstructible said:

I either a) feed my fish more or b) dissolve 10 grams of Spectracide into 1 liter of RO/DI water. I then dosed 250 ml into 150 gallons of water to raise by about 5 ppm. Hope that's helpful for you! I find that heavier feeding is the more natural way to raise nutrients

I've been feeding relatively heavily. I'm adding almost 1 cube of frozen mysis/enriched brine and other frozen types of food daily...and they already can't seem to handle it. I guess most of my fish are relatively small though (2 small clowns, firefish, royal gramma, bangaii cardinal)...and a flame angel and melanurus wrasse that are decent size. I plan on putting in an order to live aquaria...but my 3rd daughter is due any day now...and I don't think I'd survive my wife's wrath if I leave the hospital during labor...to acclimate fish.

Question...how long did you dose the 250ml for? Was it all at once or over a period of time? I was thinking of starting with 10ml of dilluted spectracide as you mentioned, once a day. Then increasing it as needed...with daily testing.

 

4 hours ago, Merman said:

In my experience undetectable nitrates are not good. I had several large colonies start to STN from the bottom up and it took me a while to figure it out. I started (slowly) dosing stump remover and the problem immediately went away and all my colonies started to recover. Also several smaller frags/colonies that were pale looked much more colorful. I’m talking within days.

Keep in mind I have a mature tank and phosphates were normal so I was dealing with an imbalance. Increasing feedings is more of a long term solution so if your situation doesn’t seem urgent that may be the way to go. For me, stump remover worked great because I needed to raise nitrates immediately and not raise phosphates. Increased feedings will raise both.

For what it’s worth I believe the root cause of my undetectable nitrates was my chaeto growing too well over a long period of time. You might also want to consider knocking down you refugium lighting schedule/intensity.


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Well that makes me slightly excited to try it! Would love to see results within a few days. Is there a similar way to raise phosphates? I can throw 2 cubes of food in a day...but I just feel that is a lot of wasted food that will get caught in the filter sock. 

I'll try pulling out more chaeto too.

 

2 hours ago, FarmerTy said:

You can dose the Spectracide but with 5 ppm of nitrates in my system via Spectracide and 5 ppm of nitrates via more fish and feeding, my corals responded better in the second scenario. That being said, in your situation, I'd go ahead and dose the nitrates up to 5 ppm. I'm a believer of low phosphate in SPS tanks like yours. Just better color and better growth IME.

Should I just double the amount I feed daily...and let all that extra food get into filter sock? My fish are already barfing up food after feedings cuz they can't handle what I'm already putting in the tank lol. 

[Reefpuck]

4 hours ago, Isaac said:

wait, weed killer as nutrient? weird.  i'd just feed more, keep it more... natural cycle.  nice side effect, you get large happy fish?

It was funny when I asked the guy at home depot who was helping me locate it...he looked at me like I was insane. I wonder if some of the other yard chemicals I have in my garage will benefit my tank as well!

[Isaac]

10 minutes ago, Reefpuck said:

It was funny when I asked the guy at home depot who was helping me locate it...he looked at me like I was insane. I wonder if some of the other yard chemicals I have in my garage will benefit my tank as well!

go look at @FarmerTy's dipping thread.

[FarmerTy]

go look at [mention=463]FarmerTy[/mention]'s dipping thread.

Pesticides, and dog dewormer, and water softener pellets, oh my!

[Timfish]

Feed your fish more or get more fish and feed them more or get rid of your cheato.  If you have undetectable nitrates it's because your corals and chaeto are sucking up all the urea and ammonia excreted by your fish and there's nothing left for nitrifying bacteria to break down into nitrates.  Corals preference is urea then ammonia then nitrates.  And keep in mind corals are phosphate limited not nitrogen limited and increasing nitrogen without increasing phosphate risks exacerbating the problem.  Increasing the amount of food fed to your fish is the safest way as it's also increasing phosphate.

[Merman]

11 hours ago, Reefpuck said:

I've been feeding relatively heavily. I'm adding almost 1 cube of frozen mysis/enriched brine and other frozen types of food daily...and they already can't seem to handle it. I guess most of my fish are relatively small though (2 small clowns, firefish, royal gramma, bangaii cardinal)...and a flame angel and melanurus wrasse that are decent size. I plan on putting in an order to live aquaria...but my 3rd daughter is due any day now...and I don't think I'd survive my wife's wrath if I leave the hospital during labor...to acclimate fish.

Question...how long did you dose the 250ml for? Was it all at once or over a period of time? I was thinking of starting with 10ml of dilluted spectracide as you mentioned, once a day. Then increasing it as needed...with daily testing.

 

Well that makes me slightly excited to try it! Would love to see results within a few days. Is there a similar way to raise phosphates? I can throw 2 cubes of food in a day...but I just feel that is a lot of wasted food that will get caught in the filter sock. 

I'll try pulling out more chaeto too.

 

Should I just double the amount I feed daily...and let all that extra food get into filter sock? My fish are already barfing up food after feedings cuz they can't handle what I'm already putting in the tank lol. 

Aw man I don't want to get your hopes up and set unrealistic expectations  You situation doesn't sound as dire as mine and I had a lot of room for improvement.

Based on the information you've given my guess would be your chaeto is outcompeting your frags.  How many frags do you have?  How long have they been there?  Your tank is relatively young and frags take some time to get acclimated and start growing.  Taking some chaeto out is a good first step but it's going to grow back eventually.  I would revisit the lighting schedule in your refugium and try to slow down the growth rate.  The more light you give it, the faster it grows and the more nutrients it consumes.

The consensus seems to be to get more fish and feed more.  Solid advice, do that (+1 on the tang).  I don't think there is too much harm in dosing some nutrients as long as you go really slow and do it over a period of time.   Add them too fast and you will likely cause an unwanted bloom.  I've never had to dose phosphate before so I don't have any advice there but you could look into what jolt suggested (Birghtwell NeoPhos).

Just to put things into perspective:  you're six months in, everything is going well, and you're getting some growth from your SPS.  Sounds pretty good to me!

[jolt]

12 hours ago, Timfish said:

Feed your fish more or get more fish and feed them more or get rid of your cheato.  If you have undetectable nitrates it's because your corals and chaeto are sucking up all the urea and ammonia excreted by your fish and there's nothing left for nitrifying bacteria to break down into nitrates.  Corals preference is urea then ammonia then nitrates.  And keep in mind corals are phosphate limited not nitrogen limited and increasing nitrogen without increasing phosphate risks exacerbating the problem.  Increasing the amount of food fed to your fish is the safest way as it's also increasing phosphate.

But, when you don't have enough fish you gotta do *something*, at least for the short term.  This is the reason I prefer Seachem Flourish Nitrogen over other additives: "Flourish Nitrogen™ is a concentrated (15,000 mg/L) blend of nitrogen sources. It provides nitrogen in both the nitrate form and the plant–preferred ammonium form. However, no free ammonia is released because the ammonium in Flourish Nitrogen™ is complexed and unavailable until utilized by the plants. Flourish Nitrogen™ also provides nitrate for those plants that can readily utilize nitrate as well."

1 hour ago, Merman said:

Aw man I don't want to get your hopes up and set unrealistic expectations  You situation doesn't sound as dire as mine and I had a lot of room for improvement.

Based on the information you've given my guess would be your chaeto is outcompeting your frags.  How many frags do you have?  How long have they been there?  Your tank is relatively young and frags take some time to get acclimated and start growing.  Taking some chaeto out is a good first step but it's going to grow back eventually.  I would revisit the lighting schedule in your refugium and try to slow down the growth rate.  The more light you give it, the faster it grows and the more nutrients it consumes.

The consensus seems to be to get more fish and feed more.  Solid advice, do that (+1 on the tang).  I don't think there is too much harm in dosing some nutrients as long as you go really slow and do it over a period of time.   Add them too fast and you will likely cause an unwanted bloom.  I've never had to dose phosphate before so I don't have any advice there but you could look into what jolt suggested (Birghtwell NeoPhos).

Just to put things into perspective:  you're six months in, everything is going well, and you're getting some growth from your SPS.  Sounds pretty good to me!

Yes, dosing too fast is a potential recipe for cyano and other nasties, especially if your tank is new and you started with dry rock!  I know this from personal experience.

[FarmerTy]

I wouldn't dose phosphate is my personal opinion. I had 0.03 ppm of phosphates, dosed nitrogen when my tank was fallow, and acros colored right up. You get enough daily phosphate from feeding, you don't need to dose it. If you're not feeding your tank, then yes, at that time I would agree that maybe adding phosphates would be beneficial.

As to nitrate and phosphate balance specifically in an acro tank, real world data in mine is 15 ppm of nitrates to 0.03 ppm of phosphates.

You got to see my tank at the meeting and when you picked up the additional frags so you know you should get similar results at those nutrient levels.

[Reefpuck]

I really appreciate the input everyone! I have lots of new things to consider and try now. I'll follow up with everyone once I have some feedback from my tank in a few weeks or so. 

And on a side note...I'm seriously impressed with the amount of feedback and help I got within a 24hr period. I always thought RC was the forum to be on (been on it for 14 years or so), but I'm starting to think I should come bug all you local reefers first. 

[Timfish]

Jolt might be right but I would encourage you to read the following papers on phosphate deficiency.  If your corals are experiencing a PO4 deficiency increasing nitrogen has the potential of bleaching or even killing your corals.  A couple things to keep in mind is while we can't test for organic nitrogen or phosphate both are almost certainly in your system.  We also can't test to see if your corals are feeding heterotrophicly (feeding off organic nitrogen and phosphate) or austotrophicly (feeding or inorganic nitrogen and phosphate).   Unfortunately this is important as this paper shows while one species may feed heterotrophicly another may not.  Corals also have simbionts in their holobiont that helps recycle nitrogen and fix nitrates from dissolved nitrogen gas.  

Phospahte deficiency 1 

An important takeaway from this first paper is corals can acclimate to conditions with unhealthy nitrogen/phosphate ratios.   An unhealthy ratio doesn't mean immediate death, it probably means brighter colors as there's fewer zooxantheallae (which is another concern as they provide an important part of the corals immune system).  It does mean an increased sensitivity bleaching and potentially death with environmental changes.  Also, what might seem counter-intuitive, the zooxantheallae, even though on a minimal diet, can provide a larger percentage of their photosynthate (sugers) to the coral for it's growth than zooxanthellae with healthier nitrogen/phosphate numbers

Phosphate deficiency 2

Phosphate deficiency 3

 

[Reefpuck]

Oh wow....Ill have to go through those in the morning after my first cup of coffee!

But I'm only looking to raise nitrates to 1-3ppm if I can control it that much. Do you think in your opinion that nitrates in  that range with 0 phosphates is a potential issue? Im not looking for 20+ nitrate levels. Also would throwing some food in the filter sock be ok... just to sit there and breakdown throughout the day?  I feel like over feeding the fish everyday is unhealthy for them.

I removed all but a golf ball size of my chaeto... and will keep it that small until I'm past this. I'll keep over feeding daily too.

 Sorry not trying to skip out on the articles you sent...it will be good reading material when I'm at the hospital all day tomorrow. 

[jolt]

10 hours ago, Timfish said:

Jolt might be right but I would encourage you to read the following papers on phosphate deficiency.  If your corals are experiencing a PO4 deficiency increasing nitrogen has the potential of bleaching or even killing your corals.  A couple things to keep in mind is while we can't test for organic nitrogen or phosphate both are almost certainly in your system.  We also can't test to see if your corals are feeding heterotrophicly (feeding off organic nitrogen and phosphate) or austotrophicly (feeding or inorganic nitrogen and phosphate).   Unfortunately this is important as this paper shows while one species may feed heterotrophicly another may not.  Corals also have simbionts in their holobiont that helps recycle nitrogen and fix nitrates from dissolved nitrogen gas.  

Phospahte deficiency 1 

An important takeaway from this first paper is corals can acclimate to conditions with unhealthy nitrogen/phosphate ratios.   An unhealthy ratio doesn't mean immediate death, it probably means brighter colors as there's fewer zooxantheallae (which is another concern as they provide an important part of the corals immune system).  It does mean an increased sensitivity bleaching and potentially death with environmental changes.  Also, what might seem counter-intuitive, the zooxantheallae, even though on a minimal diet, can provide a larger percentage of their photosynthate (sugers) to the coral for it's growth than zooxanthellae with healthier nitrogen/phosphate numbers

Phosphate deficiency 2

Phosphate deficiency 3

 

To be clear: I am not advocating dosing N & P as the right way to go long term.  I think having the right bioload of fish etc is absolutely the end goal.  It's just that personally, I don't always immediately know what that magic number of fish is when I start a new system so I feel it's good to supplement a bit until I figure that out.  I'd rather undershoot with the bioload and supplement N & P until I get up to the correct bioload than overshoot the bioload then have to go and strip the water of N & P indefinitely.  Even when dosing we should want to have N and P balanced as best we can determine, I agree 100% Tim!

Also, for others like me who actually have skimmed those papers Tim cites, you need to notice that most scientific papers report phosphate concentration in micromols which is  10⁻⁶mol/L, which you need to convert to PPM to relate to how we typically measure N and P.  I believe the calculator here can be used to convert : http://unitslab.com/node/56, where you are looking at the mg/L conversion result, which my understanding is equivalent to PPM.  So, for example in the methods section of the first reference above you will see they define low P as <0.07 micromols, which I believe converts to <0.0022 PPM which is probably ultra low by anyone's definition.  Does that sound right Tim?

[Timfish]

Jolt, what intrigues me about the research on PO4 deficency when viewed along side the research showing each species of stony coral looked at has so far individual preferences for light spectrum (color temp, K value) water flow and feeding preferences for growth each species may also have preferred ratios of organic or inorganic nitrogen and organic and inorganic ratios of phosphate for healthy growth, the studies done so far are just scratching the surface.   What got me started looking at what might make corals photosensitive and bleach was Richard L's bleaching event when he added a supplement.  I don't remember the specific supplement or reason he added it just he had some corals bleach significantly and some just a little and some didn't care.   Southhampton's research goes a long way to help explaining such events.   I don't doubt too much nitrogen can be stripped out of a system and it may need to be supplemented but we also need to be sensitive to the risks of creating an unhealthy N/P ratio.  Sadly we still don't have any way to test for organic forms to help determine the ratios in our systems. 

 

7 hours ago, Reefpuck said:

...it will be good reading material when I'm at the hospital all day tomorrow. 

You didn't stay up all night reading it!  Clearly you do not have the proper level of obsession!     Hope things go well! 

If my math is correct (the papers gave numbers in µmoles) with a PO4 level below .02 mg/l a nitrate level of just 1.6 mg/l might be enough to cause problems.  But with PO4 above .03 mg/l the zooxanthellae far less likely to have issues with higher levels of nitrate, from the third paper "it is likely that the absolute N:P ratio becomes also less critical for the proper functioning of the symbionts when phosphate concentrations exceed a vital supply threshold (> 0.3 μM)" .  Keep in mind because of the difficulty in testing for organic nitrogen and organic phosphate the researchers stopped all heterotrophic feeding and only looked at autotrophic feeding.  When applying this numbers to our systems we need to keep in mind there's variable we can't test for.  There will also be variation by species depending on feeding choices.  My recommendation (even though I don't follow it, see my recent post in Robb's thread ) is to keep PO4 between .03 to .2 mg/l.    It varies by species but inhibition of calcification appears start somehwere around .3 to .4 mg/l PO4.  And for your viewing pleasure here's this video on phosphate by a curator at the Stienhart Aquarium.

 

[jolt]

I'll say that I feel I always see issues in my frag tank if I let P hit <= 0.02 PPM, so at least for my tank I think those guys are on to something!  And, it's not every coral, just certain ones, not limited to acropora.

[Christyef]

wait, weed killer as nutrient? weird.  i'd just feed more, keep it more... natural cycle.  nice side effect, you get large happy fish?

Lol. I’m with you. I had to read that several times to make sure I read stump killer right. [emoji23][emoji23]


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[Christyef]

My N and P are high! You are welcome to have some of my Water! [emoji6][emoji23]


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