Unknown algae problem

[EEE1986]

I still can't tell, so words will have to do. :)

In person, does it look hairy or stringy?

Or instead does it look slimy and patchy?

How does it feel?

Is it stuck to the sand or can to wave it away with a wave of your hand?

It does not look hairy or stringy. More like slimy and patchy and clumped together into a semisolid concretion on top of the sand. It actually has some structural integrity to it and crumbles to pieces when disturbed. Most of it goes away at night when the lights are off. Rechecked nutrients today and they were 0.15 for P and 2.5 for N so pretty much same as last week. Definitely less on the sand today though.

 

[EEE1986]

How well is your flow across the sand bed, could be a dead spot.

It's only a 13.5 gallon tank but I have a 250gph return pump and an AI nero powerhead going between 1%-35% at high variance. When I initially picked this setting, 35% was just enough to gently move the surface of the sand but I have since added way more stuff to the tank so could be that flow needs to be audited. I just increased the max to 45% with medium variance and moved the powerhead closer to the sandbed so I will see what that does.

 

[carlog1118]

I agree, especially with all that white light in the tank combined with bottomed out nutrients is outcompeting the good bacteria in the sandbed.

This would be my guess as well. Specifically because of the nutrients bottoming out.

 

[mcarroll]

This could be Chrysophytes....does it have a brownish tink to the green? In any event, once you have a solid enough ID to your satisfaction, the bottom line will be the same – remove it as often as needed. Siphon hose should work....even using an air line.

If it is Chrysophytes, they aren't nice to corals, so stay aware of where it's growing....and keep removing it.

Microscope pics would be nice.

 

[EEE1986]

This could be Chrysophytes....does it have a brownish tink to the green? In any event, once you have a solid enough ID to your satisfaction, the bottom line will be the same – remove it as often as needed. Siphon hose should work....even using an air line.

If it is Chrysophytes, they aren't nice to corals, so stay aware of where it's growing....and keep removing it.

Microscope pics would be nice.

Depending on the lighting it definitely appears brown at times which made me think it was diatoms originally. The frogspawn in one of the affected areas looks shrunken and is constantly producing a stream of mucus so I suspect it is irritating to it but none of the other two euphyllia in the tank are thriving either and they are in separate areas

 

[EEE1986]

Update: the algae has more or less disappeared from the sand bed so I could not secure a good sample for the microscope but a wispy green/brown algae keeps on coating my dragons breath and gorgonian causing bubble entrapment. I worry it’s doing harm

 

[EEE1986]

If you have access to a microscope, or if you're willing to lay out $10+ for a new one, it would be very interesting to see photos of what you see through it.

Selecting a microscope​

I have access to one. Will post what I find over the weekend

I fear these are Dino’s but maybe an expert can confirm
View attachment 20250926_081352_AC786BB0-FDE3-4336-B073-8F1205151AA5.mov

View attachment 20250926_081507_64958727-7955-4705-92B9-0F502514A98E.mov

 

[EEE1986]

Reuploading videos so no attachments need to be downloaded

 

[Lavey29]

https://www.reef2reef.com/attachments/dinoflagellateid12_12_2019-pdf.1324729/

 

[slingfox]

Update: the algae has more or less disappeared from the sand bed so I could not secure a good sample for the microscope but a wispy green/brown algae keeps on coating my dragons breath and gorgonian causing bubble entrapment. I worry it’s doing harm

Looks like dinos. Look into the threads on how to control.

 

[mcarroll]

Yeah, I think I agree.....a post into the big dino thread should get you a more certain ID.

https://www.reef2reef.com/attachments/dinoflagellateid12_12_2019-pdf.1324729/

Is this PDF re-posted from a thread you can post or PM to me? (clicking downloads a PDF, so no thread, no comments)

 

[Lavey29]

Yeah, I think I agree.....a post into the big dino thread should get you a more certain ID.


Is this PDF re-posted from a thread you can post or PM to me? (clicking downloads a PDF, so no thread, no comments)

Dinoflagellate Identification Guide

I've had this laying around for a while. Had some recent interest, so I tweaked it a bit and am posting it. Not really about cures just ID pictures, videos, and a few short facts. Hope it can be helpful.

www.reef2reef.com