DIY Ammonia dosing for low nitrate systems

Some observations and feedback needed.

First, I've been dosing ammonium chloride for a month, and switched to ammonium bicarb this week. When dosing, I don't see a drop in pH, where I saw a .03 drop after dosing. Nice!

Second, I swear my Bubblegum Digi is a canary coral. Mag too low? Polyps close up. Light or flow issues? Polyps close up. After changing my dose from 4 drops chloride to 1ml bicarb, polyps close up. They come back out about 4 hours later.

Third, N03 is dropping. I don't think this is related to the switch. I try to maintain 5ppm N03, and I have seen a steady drop over the past week from 5 down to 3.2. Additionally, I've had to increase my kalk dosing as Alk has been dropping, too. My corals look very happy, and I'm seeing new growth so I assume it is related to this dosing.

I have some LPS in this tank for now (it will go into another tank soon) and these corals look happy. The Duncan I have had for 10 months (which never grew a new head) has sprouted 4 new heads in the last 30 days.

Fish do not exhibit any reaction to the dosing.

Given that N03 continues to drop (P04 has been dropping as well) I have increased my dose to 2x per day at 1ml per dose. I'm wondering how many doses I can do per day, and is it the correct expectation that N03 will rise after multiple doses? Of course I don't want to upset the balance of my tank or harm the fish. And I should mention no noticeable changes to green algae growth, and the coralline growth is starting to take off rapidly.
 
I think dosing more times per day is a fine plan.

Polyps closing is a concern. Might they be encountering ammonia before it dilutes enough?
I dose in the sump area of my AIO so it mixes via the return pump. I will try distributing the dose over 30 seconds and see if that makes a difference. Thanks, Randy!
 
Some observations and feedback needed.

First, I've been dosing ammonium chloride for a month, and switched to ammonium bicarb this week. When dosing, I don't see a drop in pH, where I saw a .03 drop after dosing. Nice!

Second, I swear my Bubblegum Digi is a canary coral. Mag too low? Polyps close up. Light or flow issues? Polyps close up. After changing my dose from 4 drops chloride to 1ml bicarb, polyps close up. They come back out about 4 hours later.

Third, N03 is dropping. I don't think this is related to the switch. I try to maintain 5ppm N03, and I have seen a steady drop over the past week from 5 down to 3.2. Additionally, I've had to increase my kalk dosing as Alk has been dropping, too. My corals look very happy, and I'm seeing new growth so I assume it is related to this dosing.

I have some LPS in this tank for now (it will go into another tank soon) and these corals look happy. The Duncan I have had for 10 months (which never grew a new head) has sprouted 4 new heads in the last 30 days.

Fish do not exhibit any reaction to the dosing.

Given that N03 continues to drop (P04 has been dropping as well) I have increased my dose to 2x per day at 1ml per dose. I'm wondering how many doses I can do per day, and is it the correct expectation that N03 will rise after multiple doses? Of course I don't want to upset the balance of my tank or harm the fish. And I should mention no noticeable changes to green algae growth, and the coralline growth is starting to take off rapidly.
I think that you dosing more ammonia a once is possibly the main reason for the nitrate and phosphate dropping. The ammonia distribution from ammonia dosing is very different than it coming from fish. If someone doses a tiny amount of ammonia (relative to tank size) at once enough times during a day that it adds up to a lot of ammonia, a lot of it will probably be consumed before a significant amount reaches all the corals (this is obviously true to some extent). I am leaning towards fewer larger doses of ammonia (as long as it doesn't cause any problems) instead of more smaller doses.

I think that you dosing more ammonia at once could be causing a quick enough and large enough drop (it may be partly about where the phosphate level is) in phosphate to irritate the Bubblegum Digi. I believe I have seen this before. I would recommend mixing the ammonia dose with some water and phosphate before dosing it.
 
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I think that you dosing more ammonia a once is possibly the main reason for the nitrate and phosphate dropping. The ammonia distribution from ammonia dosing is very different than it coming from fish. If someone doses a tiny amount of ammonia (relative to tank size) at once enough times during a day that it adds up to a lot of ammonia, a lot of it will probably be consumed before a significant amount reaches all the corals (this is obviously true to some extent). I am leaning towards fewer larger doses of ammonia (as long as it doesn't cause any problems) instead of more smaller doses.

I think that you dosing more ammonia at once could be causing a quick enough and large enough drop (it may be partly about where the phosphate level is) in phosphate to irritate the Bubblegum Digi. I believe I have seen this before. I would recommend mixing the ammonia dose with some water and phosphate before dosing it.

Why would the size of the individual doses impact the phosphate uptake?
 
Why would the size of the individual doses impact the phosphate uptake?
Partly because I believe that more organisms that aren't nitrifying bacteria (nitrifying bacteria don't consume much phosphate) will probably get more of the ammonia, and also the organisms would likely consume a larger amount of phosphate and/or it would allow for more areas that can better support an organism that can consume larger amounts of phosphate from more ammonia, and the organisms may significantly lower the phosphate (unlike nitrifying bacteria) from the increased growth that I believe they will likely get from the ammonia that they get.
 
Partly because I believe that more organisms that aren't nitrifying bacteria (nitrifying bacteria don't consume much phosphate) will probably get more of the ammonia, and also the organisms would likely consume a larger amount of phosphate and/or it would allow for more areas that can better support an organism that can consume larger amounts of phosphate from more ammonia, and the organisms may significantly lower the phosphate (unlike nitrifying bacteria) from the increased growth that I believe they will likely get from the ammonia that they get.

I agree that nitrifying bacteria don’t consume much phosphate, but that’s not the endpoint. The nitrate produced will go on to drive P uptake, unless you are actually accumulating nitrate.
 
I agree that nitrifying bacteria don’t consume much phosphate, but that’s not the endpoint. The nitrate produced will go on to drive P uptake, unless you are actually accumulating nitrate.
I was counting corals as some of the organisms I was talking about and also as some possible end points that could accumulate phosphate. The ammonia dosing may also increase certain bacteria in the water that I believe that a lot of corals can consume.

If I'm not mistaken, I think that you believe that adding ammonia won't, at least directly, benefit corals as long as nitrate is in an acceptable range. To me that seems like you may be practically saying that the only things that a lot of corals need in the water to grow well are nitrate and phosphate that are each kept at an acceptable level and stability, and everything in a salt mix is kept at an acceptable level and stability. To grow well I believe that all or most photosynthetic corals need more in the water than that.

I believe that most photosynthetic corals can directly benefit from ammonia by consuming it, and that at least a lot of them can consume bacteria that may grow more from dosing ammonia (benefit indirectly).
 
If I'm not mistaken, I think that you believe that adding ammonia won't, at least directly, benefit corals as long as nitrate is in an acceptable range. ....

There is evidence that corals will take up ammonia as opposed to nitrate when both are present, and it takes less energy to use ammonia than it does to use nitrate. Thus, there may be benefits of ammonia over nitrate and is, IMO, the only reason one would dose it over nitrate, which is easier to dose.
 
Hey Randy, question regarding ammonia uptake (and amino comparisons) - I typically does amino acids in the AM because lights are turning on and it’s just an easier routine for me. I have noticed that a lot of people recommend dosing amino acids at night because polyps are coming out for feeding..

1. Is the use of amino acids and ammonia a similar process for corals?
2. Is there a benefit to dosing ammonia at night?

I would assume that corals take up these nutrients in the water column via tissue, differently then a solid food and wouldn’t require polyp extension? In this case, I’d imagine the coral actively uptake aminos/ammonia more readily in the AM/afternoon?

Right now I dose ammonia in the afternoon, but trying to gauge if there is any benefit to dosing at night? Or would that end up being strictly bacteria food?
 
I agree with the uncertainty. I do not know if corals are more likely to take up dissolved amino acids at night. It might be true, but I don’t think one should assume it based on feeding tentacles being out since they will not be taken up by the particle capturing mechanism.
 
I agree with the uncertainty. I do not know if corals are more likely to take up dissolved amino acids at night. It might be true, but I don’t think one should assume it based on feeding tentacles being out since they will not be taken up by the particle capturing mechanism.
I kind of figured the time didn't matter for the corals becayse they probably don't capture it by feeding, but absorb is through tissue.

It might be the case that there is a better time to dose it based on when algae will consume it. I would guess that algae either consumes it during photosynthesis, or during resperation, but not both.
 
@Randy Holmes-Farley I am interested in dosing ammonium bicarbonate. Most of my pieces look good, but I have some that are pale and the tissue looks dry, etc. NO3 is very low, and PO4 is a little higher than I would like. Last week, NO3 tested at 0.06 (very low, usually around 15), and PO4 tested at 0.07. I decided to start feeding the system heavier daily to try and raise nutrients. I fed the tank (broadcast) daily with Benereef and Reef Roids. I waited a week to test, and NO3 dropped to 0.04 and PO4 increased to 0.10. I expected the PO4 to increase because of the reef roids, but I was expecting the NO3 to increase some instead of decreasing.

I also have a heavy export set up on the system. In a 50-gallon fuge filled with Chaeto, a large skimmer, a large bioreactor, and a large UV sterilizer. Over the weekend, I cut 95% of the Chaeto back and slowed the bioreactor feed pump down to its lowest setting in hopes this would slow the nutrient removal.

I was initially thinking of dosing sodium nitrate to try and raise NO3, but I am thinking dosing ammonium bicarbonate might be a better option. Would you agree?

The system is around 700 gallons. Would you recommend dosing throughout the day or all at once? Also, should I turn the skimmer or other filtration media off while dosing?
 
I am yet to be convinced that dosing ammonia is better than dosing nitrate, but it may be and either seems a good plan in your case.

With ammonia, I’d always spread out dosing as much as possible.
 
I am yet to be convinced that dosing ammonia is better than dosing nitrate, but it may be and either seems a good plan in your case.

With ammonia, I’d always spread out dosing as much as possible.
I think it’ll be difficult to convince one is better than the other based solely on visual observations in this scenario. “Better” will be influenced by what we consider something to be successful.

The end point for either dosing scenario is going to be nitrates (one endpoint is just faster than the other). I think the big differences are going to be that ammonia dosing carries higher risk (toxicity for fish in comparison to nitrates & dosing error), but the return is that ammonia is easier to uptake by corals and it feeds the existing nitrifying bacteria in the system.

I’ve only read about carbon dosing and havent done much research on it since I haven’t needed to do it - so I apologize if this is a dumb question lol.

Would ammonia dosing act similar to carbon dosing? At a high level it seems like it’s feeding bacteria and resulting in consumption of nutrients in the water column to convert ammonia to nitrates? I imagine carbon dosing would be more efficient since it wouldn’t result in additional nitrates. Could this method be better for reducing/controlling phosphates in a high PO4/low NO3 system?
 
I am yet to be convinced that dosing ammonia is better than dosing nitrate, but it may be and either seems a good plan in your case.

With ammonia, I’d always spread out dosing as much as possible.

Thank you. Curious about Ammonium Nitrate. Would that give the best of both worlds?
 
Thank you. Curious about Ammonium Nitrate. Would that give the best of both worlds?

I don't see a reason to prefer that to ammonia. Nitrate dosing alone is easier, but has no theoretical advantage to organisms, so combining it with ammonia to make it harder (due to multiple dosings per day) doesn't seem useful to me.
 
I think it’ll be difficult to convince one is better than the other based solely on visual observations in this scenario. “Better” will be influenced by what we consider something to be successful.

The end point for either dosing scenario is going to be nitrates (one endpoint is just faster than the other). I think the big differences are going to be that ammonia dosing carries higher risk (toxicity for fish in comparison to nitrates & dosing error), but the return is that ammonia is easier to uptake by corals and it feeds the existing nitrifying bacteria in the system.

I’ve only read about carbon dosing and havent done much research on it since I haven’t needed to do it - so I apologize if this is a dumb question lol.

Would ammonia dosing act similar to carbon dosing? At a high level it seems like it’s feeding bacteria and resulting in consumption of nutrients in the water column to convert ammonia to nitrates? I imagine carbon dosing would be more efficient since it wouldn’t result in additional nitrates. Could this method be better for reducing/controlling phosphates in a high PO4/low NO3 system?

Possible improvements might be in colors, polyp extension, algae levels, etc.

Carbon dosing lowers nitrate, ammonia dosing increases ammonia, so they are different sorts of processes.

Carbon dosing isn't especially useful for phosphate, but it is better than nothing.
 
I dose in the sump area of my AIO so it mixes via the return pump. I will try distributing the dose over 30 seconds and see if that makes a difference. Thanks, Randy!
I now believe the low polyp extension of the Bubblegum Digi was related to low P04. Looking at my test results over a week, I went from 0.06 to 0.0 and didn't notice as I test P04 every other day. I've been dosing trisodium phosphate to keep in line with my N03 level and polyps have remained extended.
 

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