Ammonium dosing is a bit overrated

[Miami Reef]

Ammonium dosing is the new flavor of the day. Everyone is touting its benefits as if it’s unlocked the missing puzzle piece to a successful reef aquarium.

Some continue dosing ammonia even when their tank is already overflowing with nitrate, and others have even started considering urea dosing, which is essentially urine, as a nitrogen source.


It’s my opinion that the trend for ammonium dosing and its usefulness is a bit blown out of proportion. The standard dose is about 0.1 ppm - 0.2 ppm ammonium per day. Some people go a bit higher, but not usually. That corresponds to an equivalent 0.36 - 0.72 ppm nitrate increase per day.

While it may seem a lot, in a tank with an incredibly high demand, might feel like chasing a moving goalpost.


I’ve seen people try battling dinos and low nitrate tanks with ammonium, and I’ve quickly noticed how much a painstakingly slow and frustrating process it’s become.

My opinion? If nitrate is especially low in an incredibly high demand tank, rather than trying to tinker with slow doses of ammonium, adjusting and testing frequently, and watching as the dinos suck up the minuscule ammonia that is added, it’s significantly easier to immediately front-load the tank with ~10 ppm NO₃ and then adjust as needed with increased fish feedings or ammonium.

I’d like to limit N limitations immediately, then worry about allowing corals to have their “preferred” N source.


Speaking of which, do corals actually need to work that much harder to use nitrate? The hobby has been dosing straight nitrate for decades, and the success rate seemed very good for corals. People back then used to treat nitrate dosing the same way as how we’re are currently treating ammonia dosing today.

In general, I think the energy corals expend to use nitrate isn’t as significant as it’s made out to be, but I haven’t looked at the research.

Does anyone actually know how much energy corals waste to convert nitrate into ammonium? I predict it’s far less than we assume.

 

[Dan_P]

Does anyone actually know how much energy corals waste to convert nitrate into ammonium? I predict it’s far less than we assume.

I have seen a number for nitrate reduction and it is big enough to hypothesize that an organism would take NH3 over NO3 given the choice. I am still waiting for a growth rate experiment to show whether it actually matters to a coral.

 

[Miami Reef]

I have seen a number for nitrate reduction and it is big enough to hypothesize that an organism would take NH3 over NO3 given the choice.

I don’t doubt that. There are studies showing corals would take ammonium over nitrate if given the choice.

I personally don’t think there should be a significant difference for coral health and growth. In any case, it’s perfectly fine to use ammonium and I do prefer it over nitrate sometimes.

However, lately I’ve been using sodium nitrate for boosting nitrate. It’s instantaneous, which I see as a benefit. I’m not a fan of tinkering with ammonium doses.

 

[Randy Holmes-Farley]

FWIW, when I have wanted to have more N, either in a dino situation or just in general to provide more availability, I’ve been dosing sodium nitrate because I’m often not around long enough at a stretch to optimize ammonia dosing.

I’m going to reinstate ammonia dosing to make up the shortfall between what I’m currently getting by feeding and the nitrate level which falls. I don’t want to decrease the refugium algae amount or lighting time or intensity, because phosphate is at the upper limit of my target range and I want it to decline a bit.

Will it be any different than dosing nitrate? Don’t know and I don’t have any expectation except that it will be all neutral while nitrate dosing boosts alk.

 

[Miami Reef]

I’ve been dosing sodium nitrate because I’m often not around long enough at a stretch to optimize ammonia dosing.

Thanks for your input. It’s scenarios like yours, either being away for long periods or just don’t like testing much, that makes nitrate dosing a good substitute.

It’s also beneficial for when you need a rapid increase, like for starving corals or dinos.

I think many people are too afraid to raise their ammonium dose, thinking it will harm their fish; this is the heart of the issue. I have a plan to make it much more easier and intuitive. I realized most of my concerns with ammonium can be alleviated by creating a new dosing approach.

I like ammonium bicarbonate because it is alkalinity neutral. That is a big plus for me.

 

[rishma]

When I need to boost nitrate, I dose nitrate. But I am tinkering with consistent low doses of ammonia again. When I dosed enough ammonia that it slowly raised nitrate (only up to 15ppm) the corals darkened and looked drab.

My nitrate is falling these days. My goal is to see if I can hold low <5ppm nitrate levels steady with a continuous ammonia dose and see what happens. For the last 6 weeks I’ve been dosing a small amount daily, but not enough to arrest the nitrate decline. Corals look great.

I’ll probably bump it up next in an another week or so.

Overrated? Maybe, I really have not followed what people are doing with it or claiming to achieve. I am having fun with it.

 

[rtparty]

As Hans Werner put it:

“While phosphate is the principal compound used for nearly all biological processes and compounds, nitrate is not. Nitrate is rather a waste product, the ashes of burnt excess nitrogen compounds.

When after mineralization there is still ammonium left, bacteria use its chemical energy to oxidize it to nitrate, which is a kind of final waste product of nitrogen cycle.”

I see no point in dosing them personally and I dosed them for years before switching to ammonia. In my old 250 it was a night and day difference how the corals reacted and grew under each regiment.

Little dino patches on the sand were almost immediately (within 24 hours) covered in cyano and then went away when dosing ammonia. Those same patches just kept growing dinos with nitrate dosing.

I dose ammonia and rarely even test nitrate. I don’t advocate that anyone else do this especially if new, but if you have a decent grasp on the concept and a little common sense, it works great IME

 

[CHSUB]

“I’m successful because of high no3”…..no, imo, you’re successful in spite of high no3. You should congratulate yourself because you are doing something that mother nature and eons of evolution can’t: growing corals with unnatural and unhealthy waste products.

We are smarter than this to continue this silly trend…corals don’t starve, dinoflagellate don’t overrun your tank because a hobby test kit shows undetectable levels of a waste product.

I agree ammonium dosing is overrated and unnecessary in a functional reef tank with fed fish but so is nitrate dosing based on hobby testing.

 

[Randy Holmes-Farley]

“I’m successful because of high no3”…..no, imo, you’re successful in spite of high no3. You should congratulate yourself because you are doing something that mother nature and eons of evolution can’t: growing corals with unnatural and unhealthy waste products.

That’s a bit of a stretch there. It’s akin to saying if I peg temp at 80.324768 I am “doing something that mother nature and eons of evolution can’t: growing corals with unnatural temperature stability”.

Just because higher nitrate does not exist in the ocean does not imply anything about how corals would do in it.

 

[rtparty]

That’s a bit of a stretch there. It’s akin to saying if I peg temp at 80.324768 I am “doing something that mother nature and eons of evolution can’t: growing corals with unnatural temperature stability”.

Just because higher nitrate does not exist in the ocean does not imply anything about how corals would do in it.

How did corals ever survive under our fake lights?

 

[rtparty]

“I’m successful because of high no3”…..no, imo, you’re successful in spite of high no3. You should congratulate yourself because you are doing something that mother nature and eons of evolution can’t: growing corals with unnatural and unhealthy waste products.

We are smarter than this to continue this silly trend…corals don’t starve, dinoflagellate don’t overrun your tank because a hobby test kit shows undetectable levels of a waste product.

I agree ammonium dosing is overrated and unnecessary in a functional reef tank with fed fish but so is nitrate dosing based on hobby testing.

Weird hill to die on but impressed by your commitment

 

[KStatefan]

“I’m successful because of high no3”…..no, imo, you’re successful in spite of high no3. You should congratulate yourself because you are doing something that mother nature and eons of evolution can’t: growing corals with unnatural and unhealthy waste products.

We are smarter than this to continue this silly trend…corals don’t starve, dinoflagellate don’t overrun your tank because a hobby test kit shows undetectable levels of a waste product.

I agree ammonium dosing is overrated and unnecessary in a functional reef tank with fed fish but so is nitrate dosing based on hobby testing.

Who are you quoting? Did a post get deleted?

 

[Randy Holmes-Farley]

How did corals ever survive under our fake lights?

A true conundrum. :)

 

[thedon986]

“I’m successful because of high no3”…..no, imo, you’re successful in spite of high no3. You should congratulate yourself because you are doing something that mother nature and eons of evolution can’t: growing corals with unnatural and unhealthy waste products.

We are smarter than this to continue this silly trend…corals don’t starve, dinoflagellate don’t overrun your tank because a hobby test kit shows undetectable levels of a waste product.

I agree ammonium dosing is overrated and unnecessary in a functional reef tank with fed fish but so is nitrate dosing based on hobby testing.

Every instance I have had of a dinoflagellate bloom has been linked to flashing zeros on my Hanna eggs. I can always tell when PO4 is getting too low in my display because my rainbow monti starts retracting polyps in the center. Probably a an evil plot coordinated by Hanna to sell more reagent!

 

[Miami Reef]

Who are you quoting? Did a post get deleted?

I’ve been very active in this thread, frequently checking if any new responses were made. I can guarantee no posts were deleted.

He was likely just making a general quote.

 

[Randy Holmes-Farley]

Who are you quoting? Did a post get deleted?

I think it’s a straw man argument. Only post deleted in this thread was a duplicate post of mine.

 

[CHSUB]

Imo and Ime, I’m yet to see and evidence that disputes Marubini and Davies 96’, “enriching water with only 1-5 mM nitrate for 30 days doubled the zooxanthellae population, reduce photosynthetic rates and decreased skeleton building by 50%”

 

[jeremie]

Nitrate enrichment does seem to have a bit more negative reports in the literature compared to other nitrogen sources.

Here are a few examples:
Context-dependent effects of nutrient loading on the coral–algal mutualism
Nitrogen Identity Drives Differential Impacts of Nutrients on Coral Bleaching and Mortality
Unravelling the different causes of nitrate and ammonium effects on coral bleaching

I personally didn’t notice any negative impact on the general health of my corals when dosing nitrate either, but some of my acros grew noticeably faster after I switched to ammonia with the same amount of nitrogen added within two weeks, and my alkalinity consumption also increased (nitrate was always undetectable in my system, so the additional consumption most likely came from calcification).

 

[Randy Holmes-Farley]

Imo and Ime, I’m yet to see and evidence that disputes Marubini and Davies 96’, “enriching water with only 1-5 mM nitrate for 30 days doubled the zooxanthellae population, reduce photosynthetic rates and decreased skeleton building by 50%”

Just an fyi, 5 mM nitrate is 310 ppm. Even 1 mM is above the top end of my 5-50 ppm target range.

 

[CHSUB]

Every instance I have had of a dinoflagellate bloom has been linked to flashing zeros on my Hanna eggs. I can always tell when PO4 is getting too low in my display because my rainbow monti starts retracting polyps in the center. Probably a an evil plot coordinated by Hanna to sell more reagent!

Yes because dinos grow without nutrients? Maybe in the Matrix, but in reality stuff doesn’t grow in and with nothingness…