Brown Stuff On Rocks

[Jerome]

I know my photo sucks it's the best my camrea could do but you can see the brown/yellowish stuff growing on it.

I have noticed this brownish yellow stuff on my rock. I don't have any coraline algae growing in some areas of my tank do to the 2 10k 150w MH which see to be to bright for it.. The coraline algae grows in all the area of the tank that doesn't get direct MH lighting. My best guess at the brown stuff was sponge.. I tried to scrap it then I found it to be hard like coraline aglae though I guess it could hard even if it is sponge. I am not sure though any guesses at what it could be...

 

[Woodstock]

Sorry, I have no idea. Hopefully someone else will chime in...

 

[Jerome]

Someone PMed me that it was an aglae bloom and a thread related to that, but I don't think that the case. It's not a nusiance algae, unless there is an encrusting algae that will "bloom". I know just about every kind of algae by site so this is something else or somehting rare. I was thinking some sort of sponge, coral or a brown variety of coraline algae if there is such a thing. My tank is dialed in 0 phosphate, silicates, and nitrates. I have great SPS growth so to say it's an aglae bloom is a guess that I don't think is right.

 

[Woodstock]

Can you borrow a better camera and get a clearer pic of it?

 

[Jerome]

I dont know anyone with a better camera I tried to take a close up shot...

Sorry it's not much better..

 

[ScottT1980]

Any polyps coming out of pores?

 

[Jerome]

I looked with a magnifiying glass I haven't seen any lights on or off

 

[jwaynet]

Hi Jerome,
It's hard to tell from the photo, but it does show a likeness to encrusting porites.
Here's a photo of mine that came with my living rock.
It's a blown-up photo and it is really hard to spot the small polyps with the naked eye.

Cheers,

Jeff

 

[jwaynet]

OK - try again :spinner:

It's in my gallery if pic doesn't show

Jeff

 

[Jerome]

I dont think it's that thanks for the imput though not many people have even taken a guess at it. I still think it's some form of encrusting ??? It looks kinda mud colored with some yellow, but it's hard and encrusted I can't scrap it off... I wonder if it's some type of brown coraline algae that's more able to handle the 10k XM MHs. I haven't been able to find any information about what it could be luckly so far it seem benign... I am guessig it's not coral because there are no polyps of any kind that I have been able to see...

 

[Jerome]

okay here a better picture maybe this will help..

 

[Woodstock]

My guess is some type of encrusting sponge. There are around 1500 different types of sponges. I would consider it beneficial and leave it alone.

 

[Woodstock]

Lots and lots of brown encrusting sponge photos...

 

[Jerome]

Thanks Woodstock!