Nitrate to fight nuisance algae?

[arking_mark]

This may be totally off base, but I'm looking for a reason why over the last 2 months I've developed nuisance algae.

Tank has been ultra-low nutrients since it was started about 2 years ago (NO3 < 10ppm, PO4 < 0.1ppm)

2.5 months ago, my NO3 dropped to 0 and nuisance algae started to slowly appear. I increased frozen feedings, reduced skimming, decreased my carbon dosing and replenished my cleaning crew.

NO3 is still at 0 and nuisance algae is still growing. All my corals are happy and growing.

Clearly NO3 isn't really 0 as nuisance algae and corals are happy...just being consumed quickly.

However, I'm thinking the tank may be Nitrate limited and reducing my ability to remove PO4 quickly enough to prevent nuisance algae. My PO4 usually < 0.05 but has been hovering much closer to 0.1 for these last 2 .5 months.

I'm wondering if dosing Ca(NO3)2 and bringing up my NO3 will enable my carbon dosing and bacteria to further reduce PO4 and help eliminate my nuisance algae.

Thoughts?

 

[Miami Reef]

This may be totally off base, but I'm looking for a reason why over the last 2 months I've developed nuisance algae.

Tank has been ultra-low nutrients since it was started about 2 years ago (NO3 < 10ppm, PO4 < 0.1ppm)

2.5 months ago, my NO3 dropped to 0 and nuisance algae started to slowly appear. I increased frozen feedings, reduced skimming, decreased my carbon dosing and replenished my cleaning crew.

NO3 is still at 0 and nuisance algae is still growing. All my corals are happy and growing.

Clearly NO3 isn't really 0 as nuisance algae and corals are happy...just being consumed quickly.

However, I'm thinking the tank may be Nitrate limited and reducing my ability to remove PO4 quickly enough to prevent nuisance algae. My PO4 usually < 0.05 but has been hovering much closer to 0.1 for these last 2 .5 months.

I'm wondering if dosing Ca(NO3)2 and bringing up my NO3 will enable my carbon dosing and bacteria to further reduce PO4 and help eliminate my nuisance algae.

Thoughts?

What kind of nuisance algae are you battling?

 

[arking_mark]

What kind of nuisance algae are you dealing with?

Bubble algae and hair algae...never had any nuisance algae prior to 2.5 months ago.

 

[Miami Reef]

Bubble algae and hair algae...never had any nuisance algae prior to 2.5 months ago.

How big is your tank (for herbivore recommendations)?

 

[Spare time]

NO3 < 10ppm, PO4 < 0.1ppm is not an ULNS. A ULNS would be more like 0-2ppm nitrate and 0-0.03 phosphate

 

[Spare time]

Algae should be limited by predation rather than resources unless you are talking about competition (in which is can be risky as who get outcompeted is not set in stone)

 

[arking_mark]

How big is your tank (for herbivore recommendations)?

400l

 

[Miami Reef]

Reef Cleaners state that Pitho Crabs are very effective and better than Emeralds for bubble algae.


I would purchase a few Mexican turbos for the hair algae.

 

[EeyoreIsMySpiritAnimal]

What kind of lights do you use? A shift in the spectrum can lead to algae...

 

[arking_mark]

What kind of lights do you use? A shift in the spectrum can lead to algae...

Kessel a360x plus Reefbrite led fillers.

 

[Randy Holmes-Farley]

For dinos, raising nutrients to boost growth of other competing organisms, such as green algae, is a good plan.

For hair algae, I do not think there's much chance increasing nitrate will decrease the hair algae.

Bubble algae does fairly well at lower nutrients, so adding nitrate may allow hair algae to outcompete the bubble algae over time, but I'm not sure that is desirable.

 

[arking_mark]

For dinos, raising nutrients to boost growth of other competing organisms, such as green algae, is a good plan.

For hair algae, I do not think there's much chance increasing nitrate will decrease the hair algae.

Bubble algae does fairly well at lower nutrients, so adding nitrate may allow hair algae to outcompete the bubble algae over time, but I'm not sure that is desirable.

So if I'm reading this correctly, feeding nitrate may exercerbate the issue? More fuel for the nuisance algae?

My theory of being NO3 limited holding back my PO4 consumption through carbon dosing and bacteria out competing for nutrients is unlikely.

 

[arking_mark]

...trying it anyway with 1ppm doses to see if I can get back to measurable Nitrate, impact to PO4, and and change to nuisance algae.

 

[Randy Holmes-Farley]

Let us know what happens.

 

[arking_mark]

Let us know what happens.

I'm expecting an increase in nuisance algae...

 

[sixty_reefer]

I'm expecting an increase in nuisance algae...

You won’t, in your situation raising your nitrates will stall the nuisance algae growth as long as you carry on carbon dosing, basically you will be using the increased bacterial growth to reduce the nutrient available to the nuisance algae.

 

[arking_mark]

You won’t, in your situation raising your nitrates will stall the nuisance algae growth as long as you carry on carbon dosing, basically you will be using the increased bacterial growth to reduce the nutrient available to the nuisance algae.

That was my original thought...but not the advice I received for the idea.

 

[sixty_reefer]

That was my original thought...but not the advice I received for the idea.

Unfortunately not many folks understand the subject. But in simple words your hole system becomes the equivalent to a refugium once enough po4, no3 and dissolved Carbon is available. Allowing for the heterotrophic bacteria to become the main species in a system assimilating nutrients, and if the dose is just right not much is available for nuisance species. This will contribute to the stall in growth and eventually die off of the nuisance.

 

[Randy Holmes-Farley]

If you drive phosphate low enough to be limiting to algae, then dosing nitrate and organic carbon might reduce green algae.

If you were not organic carbon dosing, then adding nitrate is not likely to reduce algae, IMO.

FWIW, organic carbon dosing is not usually very effective at reducing phosphate, but driven hard enough it would be.

 

[arking_mark]

If you drive phosphate low enough to be limiting to algae, then dosing nitrate and organic carbon might reduce green algae.

If you were not organic carbon dosing, then adding nitrate is not likely to reduce algae, IMO.

FWIW, organic carbon dosing is not usually very effective at reducing phosphate, but driven hard enough it would be.

I do carbon dose...the question is why the the nuisance algae appeared.

Anecdotally, the algae appeared when my Nitrate dropped to 0. However, it could even be the cause of my Nitrate dropping to zero.

In response to the zero Nitrate, I increased wet/frozen feedings and reduced skimming. Nitrate didn't budge...algae continued to grow. Again, my actions could have continued to fuel the algae.

After a month, I backed down the feedings with no affect on Algae or Nitrate.

Then a couple weeks ago I did a refresh on my cleanup crew. This may be working a little...TBD. However, my Nitrate is still zero.

So I was wondering if my tank was Nitrate limited...which was holding back the effectiveness of my carbon dosing and the ability of the bacteria to outcompete the nuisance algae.

To be fair, the nuisance algae is not taking over the tank and all the Coral is doing well.