Bacterial film? Filamentous algae? Something else?

Sierra_Bravo · Apr 13, 2018

I have noticed this white to almost transparent, very fine, hairlike substance on the underside of ledges, within holes and caves, anywhere light doesn't penetrate well and has current. I do not see any branching or stalks and it covers the surface in a uniform fashion.

I was not able to find anything online but it may be in the way I was trying to describe it in Google. Can anyone point me in the right direction?

nautical_nathaniel · Apr 13, 2018

Do you have a sixline wrasse perhaps?

Sierra_Bravo · Apr 13, 2018

It's not a mucous cacoon. I have a mystery wrasse but he sets up in a different area and while maybe a little similar looking, this is something different altogether. This is present in most low light areas throughout the liverock and doesn't degrade. If anything it has spread.

nautical_nathaniel · Apr 13, 2018

Sierra_Bravo said:
It's not a mucous cacoon. I have a mystery wrasse but he sets up in a different area and while maybe a little similar looking, this is something different altogether. This is present in most low light areas throughout the liverock and doesn't degrade. If anything it has spread.

It might be bacterial in nature then, you might be able to get rid of it with a siphon or you could possible get an invertebrate that feeds on it. I think some reef safe starfish feed on it such as a red fromia star. Directed flow will also break it apart and not allow it to colonize a large area.

Sierra_Bravo · Apr 14, 2018

These are appearing under ledges and in caves, so I wont be able to direct flow on them.

Can anyone positively ID bacterial and maybe point me towards how to find out more about them? Still not having luck on Google.

Makomek · Apr 15, 2018

Do you use any air freshener like the plug in one or similar? My tank had those white fuzzy under all over the LR when My wife used those air freshener.

Sierra_Bravo · Apr 15, 2018

Makomek said:
Do you use any air freshener like the plug in one or similar? My tank had those white fuzzy under all over the LR when My wife used those air freshener.

No cleaners or air fresheners used.

MTBake · Apr 15, 2018

Kinda odd, but I have the same thing going on. It's only on the underside of my rocks also. And in crevices. Anywhere light doesn't reach. I've never figured out what it is. Doesn't seem to cause any harm. It is easily removed with manual methods, but grows back quickly. I'm guessing this is bacterial in nature but not sure and I'm definately not an expert. I'll try to get a pic when I get home in a bit.

Sierra_Bravo · Apr 15, 2018

MTBake said:
Kinda odd, but I have the same thing going on. It's only on the underside of my rocks also. And in crevices. Anywhere light doesn't reach. I've never figured out what it is. Doesn't seem to cause any harm. It is easily removed with manual methods, but grows back quickly. I'm guessing this is bacterial in nature but not sure and I'm definately not an expert. I'll try to get a pic when I get home in a bit.

I agree it doesn't seem to harm anything or is a nuisance. I just would like to know exactly what it is to research more about it and why it occurs. I'm glad to hear someone else has seen it as well.

MTBake · Apr 15, 2018

Sierra_Bravo said:
I agree it doesn't seem to harm anything or is a nuisance. I just would like to know exactly what it is to research more about it and why it occurs. I'm glad to hear someone else has seen it as well.

I started with dry rock. How about you?

I've never seen this in any past tanks. I used live rock from Fiji back in 2004 when I first strted this hobby and carried that rock over to all other setups except this one. That's really the only difference I can think of. I still could kick myself for selling that rock! I'm having a hard time getting a decent pic of this stuff. I may need to do a video like you did. It's the same stuff for sure.

Sierra_Bravo · Apr 15, 2018

MTBake said:
I started with dry rock. How about you?

I've never seen this in any past tanks. I used live rock from Fiji back in 2004 when I first strted this hobby and carried that rock over to all other setups except this one. That's really the only difference I can think of. I still could kick myself for selling that rock! I'm having a hard time getting a decent pic of this stuff. I may need to do a video like you did. It's the same stuff for sure.

Mine was Tampa Bay Saltwater live rock straight out of the Gulf of Mexico. It's been in the tank only a year.

DiZASTiX · Apr 22, 2018

I'm having the exact same issue. Subscribed to see the responses.

waxhawreefer · Apr 23, 2018

I think it’s called bacteria flock

undermind · May 13, 2022

Hey all, any updates on this? Curious if anyone has figured out what it is or gotten rid of it?

Sierra_Bravo · May 14, 2022

undermind said:
Hey all, any updates on this? Curious if anyone has figured out what it is or gotten rid of it?

It's been a while - I had this problem about four years ago. From what I remember it lasted a few months then faded away and never came back. I never did determine why it started or why it disappeared. I can tell you there were no lasting effects or harm.