Why do we work so much on nitrifying bacteria to just replace them at a later stage

[sixty_reefer]

Thanks. Interesting thread with lots of interesting ideas, some of which get complicated to sort out.

A general data point in agreement with the thread premise, when I measured the nitrifying ability of sand - from my tank and from a LFS tank. I found that both had a low but measurable amount of traditional nitrification. A couple of tenths ppm ammonia/day - converted to NO2 and NO3 without Carbon additions. This is less than you get out of a bottle of biospira on day 1. And what you get out of a bottle of biospira on day 1 - triples or more in capacity over a ~9 day traditional ammonia feeding cycle.

So after a normal cycle - traditional nitrification of ammonia->NO2->NO3 is dominant, but over time our tanks (some of them at least - aquabiomics finds coral systems with high nitrifiers too article here) settle in to a stable system where the traditional nitrifiers occupy a small role, and uptake of ammonia by algae, corals, heterotrophs (fed by Carbon in food, C released from algae, or carbon dosing) are all also consumers of ammonia.

But the other thing that I found was that the sand - although it had low levels of nitrification, it was responsive to ammonia and sped up with repeated additions. This probably means that if I change my feeding to meatier foods, pull the algae out of my sump, cut my photoperiod in half, stop vinegar/vodka additions etc- then the sandbed nitrifiers would respond and increase in population and pick up the slack.

All this is to say that the status quo of building capacity of traditional nitrification through a bottle and cycling - then switching to fish food and never thinking about ammonia again actually isn't that bad of a system. After that, our tanks respond quite well (in terms of ammonia control) to whatever regime we impose on them after that.


(I personally would feel less good about a system I started with just heterotrophs. There's a failure mode there where if the food is too much or too meaty, then they run out of carbon and just sit there looking at excess ammonia until algae can pick up the slack. Statistics about how fast heterotrophs can grow and multiply are mostly irrelevant, since our systems stay Carbon limited.)

I completely agree with everything you said, And your last paragraph could be of great importance to new reefers not being aware of the change of bacterial nutrient needs over the course of a system.
This could be the reason why so many struggle to keep undesirable algaes under control in new systems.

 

[sixty_reefer]

Most photosynthetic marine organisms are perfectly happy taking up ammonia, and many do it preferentially to nitrate if both are present.

IMO, it is likely that corals and algae are by far the biggest consumers of ammonia in reef tanks. IMO, that is why nitrifiers decline (if they do), not because heterotrophic bacteria beat them out (except possibly if you dose readily metabolized organic carbon like acetic acid or ethanol).

On a young system without many corals that free ammonia could be problematic and cause nuisance algaes to bloom imo

 

[Randy Holmes-Farley]

On a young system without many corals that free ammonia could be problematic and cause nuisance algaes to bloom imo

Maybe. Whether it is ammonia or nitrate, elevated nutrients can encourage algae.

 

[Randy Holmes-Farley]

This could be the reason why so many struggle to keep undesirable algaes under control in new systems.

What exactly?

 

[sixty_reefer]

What exactly?

That was just me thinking out loud, it’s not important. I believe I got my reassurance on the subject of nitrifying being replaced by heterotrophic bacteria over time.

 

[Randy Holmes-Farley]

That was just me thinking out loud, it’s not important. I believe I got my reassurance on the subject of nitrifying being replaced by heterotrophic bacteria over time.

Ok

 

[Spare time]

We can’t say it for sure most of this corals nutrient needs are still unknown to us, I’m just pointing out that it could be one of the reasons some can keep them alive longer than others. If a reef aquaria will end up with heterotrophic instead of nitrifying after excess C is added maybe could be something to be looked at in the community

We can't say for sure unless someone studied it to provide some evidence but it's extremely unlikely or likely very rare given that they do not live in the water column. Corals wouldn't really have a way to capture them unless they "crawled" into the coral.

 

[Garf]

We can't say for sure unless someone studied it to provide some evidence but it's extremely unlikely or likely very rare given that they do not live in the water column. Corals wouldn't really have a way to capture them unless they "crawled" into the coral.

Hmmm;

 

[sixty_reefer]

We can't say for sure unless someone studied it to provide some evidence but it's extremely unlikely or likely very rare given that they do not live in the water column. Corals wouldn't really have a way to capture them unless they "crawled" into the coral.

Most locations were this corals thrive is dark to low light with high flow it seems to me a environment were nitrifying bacteria could thrive it’s not uncommon to see plenty of bacteria in the water column in the ocean were this corals thrive.
It’s also not uncommon in home reef aquaria to be able to increase microbes in the water column by agitating the rock surface @MnFish1 got relevant evidence that that is true.

 

[Nano sapiens]

Most photosynthetic marine organisms are perfectly happy taking up ammonia, and many do it preferentially to nitrate if both are present.

IMO, it is likely that corals and algae are by far the biggest consumers of ammonia in reef tanks. IMO, that is why nitrifiers decline (if they do), not because heterotrophic bacteria beat them out (except possibly if you dose readily metabolized organic carbon like acetic acid or ethanol).

Nearly a carbon copy of what I was typing up in response

 

[Spare time]

Most locations were this corals thrive is dark to low light with high flow it seems to me a environment were nitrifying bacteria could thrive it’s not uncommon to see plenty of bacteria in the water column in the ocean were this corals thrive.
It’s also not uncommon in home reef aquaria to be able to increase microbes in the water column by agitating the rock surface @MnFish1 got relevant evidence that that is true.

I am not stating that they don't eat bacteria/bacterioplankton, but that nitrifying bacteria, at least the kinds we use in our aquaria, do not live in the water column.

 

[sixty_reefer]

I am not stating that they don't eat bacteria/bacterioplankton, but that nitrifying bacteria, at least the kinds we use in our aquaria, do not live in the water column.

Apparently they barely live in our tank surfaces and substrates past the nitrogen cycle according to many on this thread, Never mind the water column

 

[mindme]

There's no shortage of inorganic carbon in a reef tank, unless folks let the alk get too low.

FWIW, when I've set up qt tanks for fish, I often added macroalgae as part of the ammonia removal capability. No need to focus on bacteria alone.

Sounds like a job for bryopsis.

 

[EeyoreIsMySpiritAnimal]

Apparently they barely live in our tank surfaces and substrates past the nitrogen cycle according to many on this thread, Never mind the water column

*only according to you...

 

[EeyoreIsMySpiritAnimal]

On a young system without many corals that free ammonia could be problematic and cause nuisance algaes to bloom imo

In a young system without many coral, nitrifying bacteria converts free ammonia to nitrite/trate.

Have we come full circle yet??

 

[EeyoreIsMySpiritAnimal]

Thanks. Interesting thread with lots of interesting ideas, some of which get complicated to sort out.

A general data point in agreement with the thread premise, when I measured the nitrifying ability of sand - from my tank and from a LFS tank. I found that both had a low but measurable amount of traditional nitrification. A couple of tenths ppm ammonia/day - converted to NO2 and NO3 without Carbon additions. This is less than you get out of a bottle of biospira on day 1. And what you get out of a bottle of biospira on day 1 - triples or more in capacity over a ~9 day traditional ammonia feeding cycle.

So after a normal cycle - traditional nitrification of ammonia->NO2->NO3 is dominant, but over time our tanks (some of them at least - aquabiomics finds coral systems with high nitrifiers too article here) settle in to a stable system where the traditional nitrifiers occupy a small role, and uptake of ammonia by algae, corals, heterotrophs (fed by Carbon in food, C released from algae, or carbon dosing) are all also consumers of ammonia.

But the other thing that I found was that the sand - although it had low levels of nitrification, it was responsive to ammonia and sped up with repeated additions. This probably means that if I change my feeding to meatier foods, pull the algae out of my sump, cut my photoperiod in half, stop vinegar/vodka additions etc- then the sandbed nitrifiers would respond and increase in population and pick up the slack.

All this is to say that the status quo of building capacity of traditional nitrification through a bottle and cycling - then switching to fish food and never thinking about ammonia again actually isn't that bad of a system. After that, our tanks respond quite well (in terms of ammonia control) to whatever regime we impose on them after that.


(I personally would feel less good about a system I started with just heterotrophs. There's a failure mode there where if the food is too much or too meaty, then they run out of carbon and just sit there looking at excess ammonia until algae can pick up the slack. Statistics about how fast heterotrophs can grow and multiply are mostly irrelevant, since our systems stay Carbon limited.)

Exactly! Complex ecosystems have many ways to accomplish any given process and will find the most efficient way to complete depending on the environmental factors present at any given time.

*Really enjoying the scientists' explanations!

 

[EeyoreIsMySpiritAnimal]

I would disagree the most debated bacteria on this forums tend to be nitrifying not much is debated on heterotrophic bacteria and the effects after cycling a system.

The topics posted on these, or other, forums can't be used to draw conclusions about the importance/prevalence/ understanding of ANYTHING related to reefing; the number of new/beginner reefers who post questions about cycling is high, but that does not mean there is an overall "worry about nitrifying bacteria" within the hobby.

 

[EeyoreIsMySpiritAnimal]

To clarify, this is the comment Sixty was replying to:

Erin1971Texas said:
I don't think anyone "works so much on nitrifying bacteria". We add it to new tanks if needed to create a healthy environment for fish and inverts. After that, barring a sudden increase in the bioload, most don't continue to use these products...

sixty_reefer said:
I would disagree the most debated bacteria on this forums tend to be nitrifying not much is debated on heterotrophic bacteria and the effects after cycling a system

Erin1971Texas:
The topics posted on these, or other, forums can't be used to draw conclusions about the importance/prevalence/ understanding of ANYTHING related to reefing; the number of new/beginner reefers who post questions about cycling is high, but that does not mean there is an overall "worry about nitrifying bacteria" within the hobby.

 

[sixty_reefer]

To clarify, this is the comment Sixty was replying to:

Erin1971Texas said:
I don't think anyone "works so much on nitrifying bacteria". We add it to new tanks if needed to create a healthy environment for fish and inverts. After that, barring a sudden increase in the bioload, most don't continue to use these products...

sixty_reefer said:
I would disagree the most debated bacteria on this forums tend to be nitrifying not much is debated on heterotrophic bacteria and the effects after cycling a system

Erin1971Texas:
The topics posted on these, or other, forums can't be used to draw conclusions about the importance/prevalence/ understanding of ANYTHING related to reefing; the number of new/beginner reefers who post questions about cycling is high, but that does not mean there is an overall "worry about nitrifying bacteria" within the hobby.

I’m not following you, who is worried with what?
I am referring to young to mature systems (4 to 6 months plus) that may have had the dominant bacteria responsible for depleting ammonia changed and you are referring to new systems and the nitrogen cycle.
There is no source of Carbon in modern reefs during cycling unless you were to start a cycle with the traditional shrimp that would eventually break down to a organic carbon source a few months down the cycle.

 

[Kenneth Wingerter]

This isn't to say that nitrifying bacteria are absent on a natural coral reef, or that they are completely insignificant ecologically, but rather to show that they're not particularly abundant (and therefore exert a limited influence). Check out this list of top 18 microbial genera sampled from 4 major reef microhabitats ("Variability in Microbial Community Composition and Function Between Different Niches Within a Coral Reef" https://core.ac.uk/download/pdf/78071687.pdf).

In addition to those ubiquitous and massively abundant chemoheterotrophic genera such as Pelagibacter, there's a considerable representation of photoheterotrophs (Roseobacter, Rhodopseudomonas, Rhodospirillum, Rhodobacter and perhaps at least some Roseovarius sp.) in the list.

So yeah, while I wouldn't be against adding nitrifying bacteria to a new system, I wouldn't work so hard to replace them at a later stage if they fail to persist (i.e., eventually get outcompeted by certain heterotrophs).

I get that the microbiome in an aquarium is generally very different than that of a natural reef. But for those folks that are using the natural ecosystem as a model for their captive system, and use the similarity between their system and the natural system as a metric of success, you might find this list interesting.

Maybe I'm biased because I have a huge interest in photoheterotrophs, but it appears to me from personal experience (successfully conditioning new systems exclusively with Rhodopseudomonas, Rhodospirillum and Rhodobacter) that nitrifiers such as Nitrosomonas and Nitrobacter are not absolutely essential to "cycle" a system. Actually, I'd totally be one to advocate for updating and elaborating upon what we term "cycling" to better reflect what occurs in the natural environment.