DIY Ammonia dosing for low nitrate systems

I have definitely noticed I need to dose more and more ammonia to keep N from going to zero. I may actually mix in some N so it stays up. I am having trouble keeping it above 3ppm dosing 14ml of ammonia in 90 gallons per day
My N is always 0ppm. When I started dosing ammonia, I was around 3-5ppm. I stopped being concerned a few weeks ago. I’m dosing 0.8ppm of ammonia a day. Corals are fat and happy and I’m keeping my P around 0.05ppm. Should I be worried about the 0 N?
 
My N is always 0ppm. When I started dosing ammonia, I was around 3-5ppm. I stopped being concerned a few weeks ago. I’m dosing 0.8ppm of ammonia a day. Corals are fat and happy and I’m keeping my P around 0.05ppm. Should I be worried about the 0 N?

I think that’s an open question, but maybe not. Sufficient ammonia can replace the need for nitrate.
 
I am coming around to the idea that 0 ppm nitrate is not an issue if there are other N sources, even though I’m not sure those other sources are sufficient.

My nitrate is currently falling. If it gets to zero and corals look good, I think I’m going to leave it there and see what happens.

I will not try the same thing with phosphate
 
Folks sometimes see more growth that also reduces nitrate, and in any case, the algae will be taking up N.

Do you have a picture of the tank to get an idea of the extent of the algae issues?
Thanks Randy. It's not a huge explosion of algae but definitely seeing more patches of GHA here and there, as well as some dark patches on the rocks (mystery algae) that's starting to get fuzzier since. The back sheet of coralline also has short filamentous algae growing heavier and on the powerheads. Glass films up a lot more frequently.
20250112_185644.jpg
 
Thanks Randy. It's not a huge explosion of algae but definitely seeing more patches of GHA here and there, as well as some dark patches on the rocks (mystery algae) that's starting to get fuzzier since. The back sheet of coralline also has short filamentous algae growing heavier and on the powerheads. Glass films up a lot more frequently.
20250112_185644.jpg
interesting. I thought I had seen less algae growth with ammonia but I’m not really sure. I stopped dosing ammonia about 10 days ago and it’s not clear to me if algae growth has changed.

I think the coral color is lightening up, but I’ll give it a month or 2 to be sure.

Nitrate is going down. It was never high before but it had settled closer to 10 ppm and now is less than 5 ppm.
 
Any insight into toxicity for inverts? I have an army of snails and some hermits.

Based on the 2.3ml dosed into 26g = .1ppm which is safe if well mixed. If I slightly underestimate my volume at 40g I get 40/26 X 2.3 = 3.5ml to reach .1ppm
That is slightly higher than what I am dosing daily over 6 doses. Going to add another .5ml and put it at 3.5ml/day

Still have some more water changes to do today. Will test nitrates after and dose up to 15ppm and then see what happens during the week with just the ammonia dosing and my regular feeding.
 
Any insight into toxicity for inverts? I have an army of snails and some hermits.

Based on the 2.3ml dosed into 26g = .1ppm which is safe if well mixed. If I slightly underestimate my volume at 40g I get 40/26 X 2.3 = 3.5ml to reach .1ppm
That is slightly higher than what I am dosing daily over 6 doses. Going to add another .5ml and put it at 3.5ml/day

Still have some more water changes to do today. Will test nitrates after and dose up to 15ppm and then see what happens during the week with just the ammonia dosing and my regular feeding.

I have no info suggesting inverts such as snails and hermits are more sensitive to ammonia than are fish.
 
Any insight into toxicity for inverts? I have an army of snails and some hermits.

Based on the 2.3ml dosed into 26g = .1ppm which is safe if well mixed. If I slightly underestimate my volume at 40g I get 40/26 X 2.3 = 3.5ml to reach .1ppm
That is slightly higher than what I am dosing daily over 6 doses. Going to add another .5ml and put it at 3.5ml/day

Still have some more water changes to do today. Will test nitrates after and dose up to 15ppm and then see what happens during the week with just the ammonia dosing and my regular feeding.
I have a stock solution mixed up that doses both ammonium bicarbonate and trisodium phosphate in the same solution. The strength is 1ml of solution will put in 0.2ppm ammonia and 0.1ppm phosphate into my nano. I dose this 5 times a day, 0.8ml a dose, for a total of 4ml a day. I see no issues at all with any of my inverts or fish. Running this dose, my N stays a 0.0ppm (Hanna HR) and my P stays at 0.04ppm (Hanna ULR). I have various snails (1 zebra turbo, 1 trochus, 5 astrea, 5-6 cerith, 5-6 nassarius) 1 tiny tuxedo urchin, 1 tiger conch and 6-7 small blue legged hermits. No one reacts any different when the pump goes off that doses the NH3/P mixture. Business as usual other than the LPS puff up right after a dose most of the time.
 
I have a stock solution mixed up that doses both ammonium bicarbonate and trisodium phosphate in the same solution. The strength is 1ml of solution will put in 0.2ppm ammonia and 0.1ppm phosphate into my nano. I dose this 5 times a day, 0.8ml a dose, for a total of 4ml a day. I see no issues at all with any of my inverts or fish. Running this dose, my N stays a 0.0ppm (Hanna HR) and my P stays at 0.04ppm (Hanna ULR). I have various snails (1 zebra turbo, 1 trochus, 5 astrea, 5-6 cerith, 5-6 nassarius) 1 tiny tuxedo urchin, 1 tiger conch and 6-7 small blue legged hermits. No one reacts any different when the pump goes off that doses the NH3/P mixture. Business as usual other than the LPS puff up right after a dose most of the time.
Thanks for the reply! That's good news and interesting observation on the LPS reaction. So if I understand correctly, you are dosing .16ppm ammonia with each dose for a total of .8ppm/day. Seems like I have quite a long way to go to get anywhere near that at .1ppm/day currently. I appreciate the feedback on your inverts!
 
EDIT : I've decided not to follow through with this plan. Corals are growing very well so I'm just going to keep doing what I'm doing for now.


I'm going to try this out on my acro dominant tank tank that tends to run low N and P. I've been dosing sodium nitrate off and on when I see 0 but I'm going to try and see if I can dial in a maintenance dose of ammonium to keep NO3 at least above 0. I'll be using food grade ammonium bicarbonate. Total water volume is 65g. I've mixed the solution per Randy's instructions but scaled it down to a 500 ml batch. Last test had NO3 at 0.4 using Hanna HR tester. I'm going to start with 6ml ammonium daily spread out in 6 doses between noon and 10pm. Math isn't my strong suit but I think that should add just over 0.36 ppm NO3 feel free to check the math ;)
I'll be dosing manually but if I can get it dialed in I'd like to use the spare head on my reefdose 2.

We'll see how it goes.
PXL_20250115_024722901~2.jpg
 
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I generally try not to draw conclusions from making small changes - with reef tanks being so complex and all. However, everytime my SPS start losing colour, I check my nitrates and they are always 0. I add calcium nitrate, and within 48 hours, they have coloured up again.

I'm really glad Randy posted this, because although I didn't go with ammonia, I decided to try doing nitrate and it's made a big difference.
 
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I have switched back to nitrate to see the difference but I noticed an increase in hair algae and dinos on the algae when dosing ammonia. Since switching back to nitrate I have noticed the algae slowing and dinos fading. Corals look no different so far. I may go with a mix in the future. I think there is benefit to keeping nitrate a little elevated. With ammonia only my nitrate was dropping to zero no matter the dose.
 
I found some reagent grade (98% pure) Loudwolf sodium phosphate mono basic NaH2PO4 for cheap. I ordered it just to see if there was a difference. I mixed the same recipe as I was doing with the ammonium bicarbonate and trisodium phosphate, 6.6g ammonium bicarbonate and 1.1g sodium phosphate mono basic into 250ml rodi water. This mixture mixes clear unlike the trisodium phosphate mixture. There is also very little ammonia smell from this mix, it’s there, but very faint. It is crazy strong with the trisodium phosphate mixture.

One thing I did notice is that this new mixture makes a ton of gas, I assume it’s CO2, but the bottle I’m shaking it in keeps pressurizing. I have to crack the lid.

But to answer my own question, the mono basic does mix clear with very little percipient.

I have been dosing this mixture (ammonium bicarbonate and trisodium phosphate) with a single dosing pump and it is working wonderfully! So much easier than manually putting it in daily and without having to buy a second dosing pump!
 
I found some reagent grade (98% pure) Loudwolf sodium phosphate mono basic NaH2PO4 for cheap. I ordered it just to see if there was a difference. I mixed the same recipe as I was doing with the ammonium bicarbonate and trisodium phosphate, 6.6g ammonium bicarbonate and 1.1g sodium phosphate mono basic into 250ml rodi water. This mixture mixes clear unlike the trisodium phosphate mixture. There is also very little ammonia smell from this mix, it’s there, but very faint. It is crazy strong with the trisodium phosphate mixture.

One thing I did notice is that this new mixture makes a ton of gas, I assume it’s CO2, but the bottle I’m shaking it in keeps pressurizing. I have to crack the lid.

But to answer my own question, the mono basic does mix clear with very little percipient.

I have been dosing this mixture (ammonium bicarbonate and trisodium phosphate) with a single dosing pump and it is working wonderfully! So much easier than manually putting it in daily and without having to buy a second dosing pump!

Yes, trisodium phosphate is a higher pH solution than the same amount of the monosodium phosphate you now have. That seems a good choice for combining. It is releasing some CO2, which makes sense.
 
Does dosing trisodium phosphate and ammonia chloride in these relatively small amounts have a significant impact on the tanks salinity, especially when also using 2 part?
 
Does dosing trisodium phosphate and ammonia chloride in these relatively small amounts have a significant impact on the tanks salinity, especially when also using 2 part?

No.

sodium is normally in the 10,000 ppm range and chloride 20,000 ppm .
For every 1 ppm of phosphate increase with trisodium phoshate you would raise sodium about .75 ppm
For every 1 ppm of ammonia increase with ammonia chloride you raise chloride about 3 ppm
 
Does dosing trisodium phosphate and ammonia chloride in these relatively small amounts have a significant impact on the tanks salinity, especially when also using 2 part?

Agree with above analysis. The amounts are just too small. :)
 
My nutrients continue to plummet....no color at all on a Salifert NO3 test and now my PO4 is down to 0.01-0.02 the past week. But I highly doubt corals are starving....they all look better than ever and I'm seeing tremendous growth from the acros....chasing dkh with AFR dose increases, and I have to scrape the glass almost daily.
 

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