DIY Ammonia dosing for low nitrate systems

[jazzman7838]

You mean ammonia and phosphate together ? That may grow algae, and is more likely to grow bacteria. Will that happen, I don’t know.

Thank you, yes, the DI water in the ATO has ammonium bicarbonate and trisodium phosphate in it.

My tank consumes 4 dKH of alkalinity and more than 0.1 mg/L of phosphate every day. I’m having to dose a TSP solution twice daily just to keep phosphate from hitting zero. So it seems easier to add it to the ATO. I’ll report back what I see.

 

[Randy Holmes-Farley Verified Community Expert]

Thank you, yes, the DI water in the ATO has ammonium bicarbonate and trisodium phosphate in it.

My tank consumes 4 dKH of alkalinity and more than 0.1 mg/L of phosphate every day. I’m having to dose a TSP solution twice daily just to keep phosphate from hitting zero. So it seems easier to add it to the ATO. I’ll report back what I see.

Sounds good!

 

[Battlecorals Verified Sponsor]

I have decided to start dosing ammonium bicarbonate in my main system as well and I’m still a little fuzzy on nitrate testing moving forward.

and, I’m sorry if I missed it. I tried to skim this thread as best I could.

but my question is, while adding ammonium bicarbonate and say my nitrate is steady at around 6.0 when I was dosing actual nitrate. Should I expect my nitrate levels to say the same or will they fall to zero without continuously adding nitrate in lieu of the ammonium bicarbonate?

I guess I’m just not exactly sure what I should be testing for or shooting for at this point with regards to actual nitrate levels

 

[A_Blind_Reefer]

I have decided to start dosing ammonium bicarbonate in my main system as well and I’m still a little fuzzy on nitrate testing moving forward.

and, I’m sorry if I missed it. I tried to skim this thread as best I could.

but my question is, while adding ammonium bicarbonate and say my nitrate is steady at around 6.0 when I was dosing actual nitrate. Should I expect my nitrate levels to say the same or will they fall to zero without continuously adding nitrate in lieu of the ammonium bicarbonate?

I guess I’m just not exactly sure what I should be testing for or shooting for at this point with regards to actual nitrate levels

My experience was that it took complete place of adding sodium nitrate. I started by cutting my nitrate dosing in half when I first started, but I don’t think that’s necessary at all. I haven’t dosed any sodium nitrate in over six months. After my initial start at trying to maintain around 5ppm nitrate, I’ve settled on around 15-ish. I’ve had zero ill effects at all whatsoever. I’ve been using ammonium chloride but I may switch over to ammonium bicarbonate when I run out. I can’t tell if there’s been a difference between sodium nitrate and ammonium chloride in my tank due to my eyesight but I think it’s been positive based on visitors comments. Randy is the man to an ask/answer as to how far one can go. The initial basis was for low nutrient systems, but I’ve read some that are nowhere near what I envision as low nutrient.

 

[Northern Flicker]

Hi Randy, I remember you reading somewhere that for every 50 nitrates you go up, you will go up 2.3 dkH. Is this correct?

So if you know how many ppm Nitrate you are going to go up, can you calculate the effect on your dkH with:

NewAlk = ppm Nitrate increase * 0.046

0.046 just being 2.3dkH/50ppm Nitrate


EDIT: oh just read the below that it's the ammonia dosing itself that depletes Alk, not the Nitrate level itself

 

[drawman]

I have decided to start dosing ammonium bicarbonate in my main system as well and I’m still a little fuzzy on nitrate testing moving forward.

and, I’m sorry if I missed it. I tried to skim this thread as best I could.

but my question is, while adding ammonium bicarbonate and say my nitrate is steady at around 6.0 when I was dosing actual nitrate. Should I expect my nitrate levels to say the same or will they fall to zero without continuously adding nitrate in lieu of the ammonium bicarbonate?

I guess I’m just not exactly sure what I should be testing for or shooting for at this point with regards to actual nitrate levels

I think it's all a matter of whether or not you have a surplus. If your coral are consuming all of your ammonia then nitrate won't rise (and may fall).

If you're worried about an over dose after a single dose then test for ammonia.

If you're looking to see if you're adding too little or too much over the course of a day or days then test nitrate.

 

[drawman]

@Randy Holmes-Farley I'm reposting this in case you missed it...

Randy I just want to confirm that I didn't read it wrong but will both recipes be net neutral on pH and alkalinity? I'm using ammonium chloride but if bicarbonate is better for pH or different with alk I may consider switching.

Also I want to give an update I've been dosing about 1mL of ammonium chloride 2x daily (along with raising PO4). Nitrate has tested zero and still does and PO4 I've been sitting between 0.05 and 0.1ppm up from about 0.01-0.03. Algae of course is noticeably darker but I've noticed polyps coming out on some previously stalled smooth skin acros. It's a trend in the positive direction but I will keep updating here.

 

[Randy Holmes-Farley Verified Community Expert]

@Randy Holmes-Farley I'm reposting this in case you missed it...

Randy I just want to confirm that I didn't read it wrong but will both recipes be net neutral on pH and alkalinity? I'm using ammonium chloride but if bicarbonate is better for pH or different with alk I may consider switching.

Also I want to give an update I've been dosing about 1mL of ammonium chloride 2x daily (along with raising PO4). Nitrate has tested zero and still does and PO4 I've been sitting between 0.05 and 0.1ppm up from about 0.01-0.03. Algae of course is noticeably darker but I've noticed polyps coming out on some previously stalled smooth skin acros. It's a trend in the positive direction but I will keep updating here.

Ammonium chloride depletes alk. Ammonium bicarbonate is alk neutral as long as nitrate is stable.

 

[Randy Holmes-Farley Verified Community Expert]

I think it's all a matter of whether or not you have a surplus. If your coral are consuming all of your ammonia then nitrate won't rise (and may fall).

If you're worried about an over dose after a single dose then test for ammonia.

If you're looking to see if you're adding too little or too much over the course of a day or days then test nitrate.

Right. Dose just right, nitrate is stable. Dose too much and it rises. Dose too little and it falls.

 

[drawman]

Ammonium chloride depletes alk. Ammonium bicarbonate is alk neutral as long as nitrate is stable.

I better be checking my alk more often then!

 

[A_Blind_Reefer]

I better be checking my alk more often then!

For me it was only a minor adjustment but this is why I’m thinking of switching to ammonium bicarbonate when I’m out of ammonium chloride. It just feels counterproductive in my teeny little brain ha. Reality has been not that bad (as far as the gross effect on Alk) at all.

 

[Battlecorals Verified Sponsor]

Right. Dose just right, nitrate is stable. Dose too much and it rises. Dose too little and it falls.

excellent thanks! this is exactly the answer I was looking for. will report back after a few week or so for sure.

 

[John Biddle]

excellent thanks! this is exactly the answer I was looking for. will report back after a few week or so for sure.

My understanding, open to correction of course I'm far from an expert, is that the reason to dose ammonium (bicarbonate or chloride) is that corals prefer to get their nitrogen from ammonium over nitrite and even more so over nitrate. That's because the coral must first convert the nitrite or nitrate to ammonium before it can be used, but doesn't have to when using ammonium directly. This wastes coral energy and would be avoided if possible.

If you have no tank NO3, you don't know if you are nitrogen limited (not as much nitrogen as the corals want). That is, there might be unmet desire for more nitrogen. I would think, perhaps naively, that nitrogen being limited would to some extent limit growth and/or health. At 0 NO3 you probably are N limited, but you don't know the extent to which it's true. In that situation you might want to first up your nitrate dosage gradually until your tank NO3 rises and stop the increase when it settles where you want it to.

Then, or if you are already at a steady NO3 tank value that you are comfortable with, dosing ammonium is just a replacement for dosing NO3 and as your ammonium dose goes up the NO3 dose must correspondingly go down to maintain the equilibrium, whatever value it's at. @Randy Holmes-Farley may be able to provide an equivalence equation for how much to adjust one for the other to keep the balance and avoid trial by error.

I would think, again perhaps naively, that we would want to provide as much nitrogen via ammonium as the corals want to take up, so long as we can do it safely, ammonium being toxic to fish, inverts and corals. Low levels of ammonium are hard/impossible to test for at the hobbyist level so erring on the safe side is advised. Randy has offered up his recommendations early in this thread but if I remember correctly recommends dosing to bring the tank to 0.1 ppm ammonium, but thinks 0.2 ppm would also be safe and thinks 0.3 ppm doses may be as well.

 

[Koty]

Just a comment: The added ammonium is assimilated mainly into proteins mostly used for the growth of whoever is in the tank (bacteria, algae, corals, fish...). Nitrate is a waste product, and thus, the relationship of adding ammonium to the increase of nitrate may be very complex. I myself prefer to add a mix of amino acids that are a nitrogen source that is taken directly by corals and (unfortunately) by other critters in the tank. I would say that if you are adding ammonium and your nitrate stays at or near 0, it's a good spot to keep your tank.
More specifically, as an example, I dose 10-12mls /400 liters per day Tropic Marin Aminos, and my nitrate is hovering around 0.

 

[Randy Holmes-Farley Verified Community Expert]

Just a comment: The added ammonium is assimilated mainly into proteins mostly used for the growth of whoever is in the tank (bacteria, algae, corals, fish...). Nitrate is a waste product, and thus, the relationship of adding ammonium to the increase of nitrate may be very complex. I myself prefer to add a mix of amino acids that are a nitrogen source that is taken directly by corals and (unfortunately) by other critters in the tank. I would say that if you are adding ammonium and your nitrate stays at or near 0, it's a good spot to keep your tank.
More specifically, as an example, I dose 10-12mls /400 liters per day Tropic Marin Aminos, and my nitrate is hovering around 0.

As John notes above, the idea of tracking nitrate is to ensure that enough ammonia is added. The goal is not to have nitrate for use, but to just use it as a marker of adequate dosing. If it is zero, you do not know if you are adding enough.

 

[Koty]

As John notes above, the idea of tracking nitrate is to ensure that enough ammonia is added. The goal is not to have nitrate for use, but to just use it as a marker of adequate dosing. If it is zero, you do not know if you are adding enough.

True. But since I am adding X3 the recommended dose of N source it’s safe to assume that it will not be a limiting factor in the tank (IMO).

 

[Randy Holmes-Farley Verified Community Expert]

True. But since I am adding X3 the recommended dose of N source it’s safe to assume that it will not be a limiting factor in the tank (IMO).

Ok, if you trust that they somehow understand the needs of your tank. I personally cannot see how random directions can do that without being adjusted for the tank needs.

 

[Koty]

I agree. I gradually arrived at this dosing level so that my high phosphate (0.2 ± 0.05bppm) would not "be left alone" to dosing carbon. The important readout for me is that my corals look OK, and alkalinity consumption is relatively stable. I am using the Hanna high-range nitrate, so it is safe to assume that 0 is just below the range. Also, I have many fish that are heavily fed, so 0 nitrate is a surprising achievement of all my export methods.

 

[Randy Holmes-Farley Verified Community Expert]

Sounds good. There's nothing inherently wrong with nitrate below 2 ppm, as long as organisms get enough N. The ocean, after all, if below 2 ppm nitrate.

 

[machmachmach]

Hi @Randy Holmes-Farley,

I have a 265 gallon system and would like to start dosing ammonium bicarbonate. It seems like your solution is far below the maximum solubility of ammonium bicarbonate. Is there any issue with mixing it roughly 10x stronger? Wikipedia suggests 24.8g/100mL at 25C is the maximum solubility.

I have limited sump space and it would be ideal to not have to have a gallon jug for this solution. I would be dosing in the middle of my sump so I think the odds of a high concentration solution affecting fish prior to circulation seems low.

Thanks!