Help ID this pest algae (microscope images included)

[ilyad]

Hi all,

I've had a hard time with a pest algae in the tank for a very long time now... At one point this stuff took over my entire rocks to the point that manual removal was no longer sustainable. I ended up replacing my rocks with a new set of cured rocks and cleaned a lot of the frags/colonies with hydrogen perxoide and put them into my tank. A few weeks ago, I began to see some small parts of the same algae coming back, so this time I decided to nuke it before it became a bigger problem. I used Flux (because I think it is green hair algae) and had it going for 2 weeks, but it made 0 impact on it, not even slighly discolored. So I went to my LFS and put some under the microscope and got these images... any idea on whether it is GHA or something else?

As a side note, I have a ton of snails, a few urchins, a starry blenny, and white tail bristletooth and they dont seem to care for it one bit, at least not enough to make a dent in it.

TLDR: weird algae (possibly GHA) took over rocks, replaced rocks but its starting to come back. Frags were cleaned with H2O2, CUC doesnt seem to care for it, fish dont like it either. 2 weeks of Flux did nothing to it.

Zoomed out under white light

Microscope images:

It seems to have some sorts of little brown things on the strands as well:

Even higher magnification (especially parts that have brown bits on it):

Old rocks that have been taken over (this was before I removed them from the tank):

Any help to ID and possible solutions are appreciated.

 

[crazyfishmom]

That looks like plain old green hair algae to me.

What are the nutrient levels in your tank like?

 

[ilyad]

That looks like plain old green hair algae to me.

What are the nutrient levels in your tank like?

Nitrates hover around 5, and phosphates around 0.006, slightly on the lower side, but youd think then the GHA wouldnt grow as much. When the rocks were full of them, I assumed that the algae was likely pulling it out of the water column, but since replacing the rocks (months ago), the nutrients havent really gone up.

 

[crazyfishmom]

Nitrates hover around 5, and phosphates around 0.006, slightly on the lower side, but youd think then the GHA wouldnt grow as much. When the rocks were full of them, I assumed that the algae was likely pulling it out of the water column, but since replacing the rocks (months ago), the nutrients havent really gone up.

That is definitely odd. What do you have for filtration? In systems like yours some macro algae can potentially help turn the tide. Really really weird though!

 

[ilyad]

That is definitely odd. What do you have for filtration? In systems like yours some macro algae can potentially help turn the tide. Really really weird though!

For filtration, I have my water going through filter floss, then a skimmer, and finally a a bit of carbon. Unfortunately, my sump doesnt allow for a space for either a algae turf scrubber or fuge. I can possibly put some macro in the display, but I would imagine the bristletooth would munch on that really quickly

 

[crazyfishmom]

For filtration, I have my water going through filter floss, then a skimmer, and finally a a bit of carbon. Unfortunately, my sump doesnt allow for a space for either a algae turf scrubber or fuge. I can possibly put some macro in the display, but I would imagine the bristletooth would munch on that really quickly

There are little acrylic boxes that you can put macro in within your display or sump but I’m not sure that it would do very much in a tank that size. It’s a frustrating problem for sure.

 

[taricha]

pretty normal GHA (derbesia) with some diatoms growing on it.

 

[Dan_P]

Hi all,

I've had a hard time with a pest algae in the tank for a very long time now... At one point this stuff took over my entire rocks to the point that manual removal was no longer sustainable. I ended up replacing my rocks with a new set of cured rocks and cleaned a lot of the frags/colonies with hydrogen perxoide and put them into my tank. A few weeks ago, I began to see some small parts of the same algae coming back, so this time I decided to nuke it before it became a bigger problem. I used Flux (because I think it is green hair algae) and had it going for 2 weeks, but it made 0 impact on it, not even slighly discolored. So I went to my LFS and put some under the microscope and got these images... any idea on whether it is GHA or something else?

As a side note, I have a ton of snails, a few urchins, a starry blenny, and white tail bristletooth and they dont seem to care for it one bit, at least not enough to make a dent in it.

TLDR: weird algae (possibly GHA) took over rocks, replaced rocks but its starting to come back. Frags were cleaned with H2O2, CUC doesnt seem to care for it, fish dont like it either. 2 weeks of Flux did nothing to it.

Zoomed out under white light

Microscope images:

It seems to have some sorts of little brown things on the strands as well:

Even higher magnification (especially parts that have brown bits on it):

Old rocks that have been taken over (this was before I removed them from the tank):

Any help to ID and possible solutions are appreciated.

If the CUC don’t eat this algae, what are they eating instead?

 

[ilyad]

pretty normal GHA (derbesia) with some diatoms growing on it.

Any idea why Flux didnt have any impact on it? Would it be a good idea to do a second dose? Higher concentration? Should I do a water change before that, or just add more flux...

I added a dosage based on 75 gal 2 weeks ago.

 

[ilyad]

If the CUC don’t eat this algae, what are they eating instead?

They may eat some of it... but for the most part theyre sticking to the glass and back walls and eating all the film algae.