Algae ID - Brown stringy algae

[esolo16]

Hi all,

I have some algae growing on one of my rocks, but not any other rock or my sand bed. The algae is brown and stringy, almost looks mucusy (not sure if that's a word). The rock is located in high flow and has been in my tank the whole time it has been setup (around 7 months) and was cured for a couple months before going in. It could be dinos but I do not see any air bubbles in it, which I believe is one of the ways to identify dinos. It also does not seem to be bothering my corals and I do not carbon dose. Is it possible this rock is leaching phosphates and causing the algae?

Tank details:

IM Nuvo 20
ATI Sunpower 4x24
Cadlights PLS-50 Elite Skimmer
Small Refugium in one of the chambers
Running small amount of GAC and GFO in mesh bag

ph: 7.9-8.1 (Apex)
Alk: 8 dkh (Hanna)
Cal: 430 ppm (Red Sea)
Mag: 1350 (Red Sea)
PO4: .03 (Hanna)
NO3: Undetectable (NYOS)

Any help would be appreciated. Thanks!

 

[esolo16]

Crappy phone pic is all I can get

 

[twilliard]

Can you get a shot with no blue light?

 

[esolo16]

These are a little better

 

[twilliard]

It may be a species of dinoflagellates but it is hard to tell. I would have to see a microscope image.

 

[saltyfilmfolks]

IMO normal kinda. scrub it siphon and get more snails.

edit no its not a leaching thing. its imo usually not seen part of the micro fauna in the tank.

 

[esolo16]

Unfortunately, I do not have a microscope. If the algae starts getting out of hand or bothering my corals, I may have to buy one though.

I will continue siphoning during water changes for now, and may boost my CUC as well.

Thanks for all the input!