Micro algae’s blooms in aquaria are directly connected to a CNP limitation.

[sixty_reefer]

What is the evidence that denitrifying bacteria die or go dormant or even influenced the growth of micro algae?

There is many papers that support this, but logic should be enough to describe the problem, denitrification uses No3 to breathe in anoxic conditions, what do you think it will happen to any heterotrophic organism that can’t breathe?

I’m not sure if “influence” would be the most appropriate word to describe it. Basically if denitrification can’t happen it will lead to a build up of Nitrogen.
For a bloom to develop it has many variables, it’s not always certain what organism will bloom. It could be that it will just allow GHA to grow faster as a example.

 

[Randy Holmes-Farley]

There is many papers that support this, but logic should be enough to describe the problem, denitrification uses No3 to breathe in anoxic conditions, what do you think it will happen to any heterotrophic organism that can’t breathe?

I’m not sure if “influence” would be the most appropriate word to describe it. Basically if denitrification can’t happen it will lead to a build up of Nitrogen.
For a bloom to develop it has many variables, it’s not always certain what organism will bloom. It could be that it will just allow GHA to grow faster as a example.

This all seems identical to the idea that excess nitrate and phosphate will cause a bloom. It doesn’t.

 

[sixty_reefer]

This all seems identical to the idea that excess nitrate and phosphate will cause a bloom. It doesn’t.

That’s not absolutely correct, if I was to add the original Guillards f2 to a photoreactor any of this organisms can bloom in excess nutrients, depending on which micro algae is added to the photo reactor.
There is no denitrification present in those reactors, but if added to a balance tank they will never bloom. Why?

 

[Dan_P]

There is many papers that support this, but logic should be enough to describe the problem, denitrification uses No3 to breathe in anoxic conditions, what do you think it will happen to any heterotrophic organism that can’t breathe?

You are forgetting that bacteria can switch between using nitrate and oxygen as electron acceptors.

I’m not sure if “influence” would be the most appropriate word to describe it. Basically if denitrification can’t happen it will lead to a build up of Nitrogen.
For a bloom to develop it has many variables, it’s not always certain what organism will bloom. It could be that it will just allow GHA to grow faster as a example.

Your post implies denitrifiers influence algae blooms, otherwise why mention them?

 

[Dan_P]

This all seems identical to the idea that excess nitrate and phosphate will cause a bloom. It doesn’t.

Exactly. Benthic micro algae blooms cannot be predicted from water chemistry alone.

 

[sixty_reefer]

Your post implies denitrifiers influence algae blooms, otherwise why mention them?

The suggestion is that a limitation to denitrification can lead to blooms (not always) and that after the bloom occurs we can determine which limiting nutrient caused the bloom.

 

[Dan_P]

That’s not absolutely correct, if I was to add the original Guillards f2 to a photoreactor any of this organisms can bloom in excess nutrients, depending on which micro algae is added to the photo reactor.
There is no denitrification present in those reactors, but if added to a balance tank they will never bloom. Why?

Another invalid assumption here. Pelagic blooms but not benthic blooms can be predicted by water chemistry.

 

[Dan_P]

The suggestion is that a limitation to denitrification can lead to blooms (not always) and that after the bloom occurs we can determine which limiting nutrient caused the bloom.

This is still a post hoc fallacy

 

[sixty_reefer]

Another invalid assumption here. Pelagic blooms but not benthic blooms can be predicted by water chemistry.

that’s not absolutely correct, most would be able to predict the effects of adding a macro algae to a Refugium in certain conditions.

 

[sixty_reefer]

This is still a post hoc fallacy

I did write this on the first post

“I’m open to hearing a different perspective.“

Do you have a better interpretation on why many organism bloom under the same nutrient depleted conditions that affect mainly heterotrophic bacteria in aquaria?

 

[Dan_P]

that’s not absolutely correct, most would be able to predict the effects of adding a macro algae to a Refugium in certain conditions.

Irrelevant to our discussion.

 

[rishma]

This all seems identical to the idea that excess nitrate and phosphate will cause a bloom. It doesn’t.

Attempting to follow along here…

Excess nitrate and phosphate don’t cause algae blooms? Maybe I don’t know what blooms are. Do blooms refer to suspended/water born algae? My simple view has been excess nitrate and phosphate do result in algae problems. Hair algae in my current tank it seems….

 

[Dan_P]

Do you have a better interpretation on why many organism bloom
under the same nutrient depleted conditions

This is the problem. We don’t know what the nutrient conditions are. Just assumptions upon assumptions.

that affect mainly heterotrophic bacteria in aquaria?

More assumptions upon assumptions. What studies have demonstrated that mainly heterotrophic bacteria are affected by the unknown nutrient depleted conditions?

 

[Randy Holmes-Farley]

That’s not absolutely correct, if I was to add the original Guillards f2 to a photoreactor any of this organisms can bloom in excess nutrients, depending on which micro algae is added to the photo reactor.
There is no denitrification present in those reactors, but if added to a balance tank they will never bloom. Why?

That’s not even close to the statement I was addressing, but for one we do not know if this is true, and if so, there are many possible explanations unrelated to denitrification. Removal of phytoplankton by skimmers, uv, filter feeders, etc all can at a role in why many folks do not see a phyto bloom.

 

[EeyoreIsMySpiritAnimal]

There is many papers that support this, but logic should be enough to describe the problem, denitrification uses No3 to breathe in anoxic conditions, what do you think it will happen to any heterotrophic organism that can’t breathe?

I’m not sure if “influence” would be the most appropriate word to describe it. Basically if denitrification can’t happen it will lead to a build up of Nitrogen.
For a bloom to develop it has many variables, it’s not always certain what organism will bloom. It could be that it will just allow GHA to grow faster as a example.

GHA is not a microalgae

 

[rishma]

Ah, phyto bloom. Now I know what we are talking about…but since I have so rarely rarely seen that occur in my tanks I think I am going back to the peanut gallery now.

 

[Randy Holmes-Farley]

Ah, phyto bloom. Now I know what we are talking about…but since I have so rarely rarely seen that occur in my tanks I think I am going back to the peanut gallery now.

That was my assumption based on the word bloom. I’ve only heard that in the context of bacteria or algae in the water, but that may be my misinterpretation.