Brown Algae or not

[fernalfer]

Ok i have a 120 gallon tank that has some brown on the sand and tons of rock with no hair algae or green algae. It has some brown stuff on it. It does not dust of with a turkey baster it is actually hard like almost encrusted onto the rock. Does Brown algae sometimes do this?

I will post pick when white lights come on. If you look at my rocks they look algae free but with a brownish tint. Definitely not diatoms because they don't brush off.

 

[saltyfilmfolks]

Ok i have a 120 gallon tank that has some brown on the sand and tons of rock with no hair algae or green algae. It has some brown stuff on it. It does not dust of with a turkey baster it is actually hard like almost encrusted onto the rock. Does Brown algae sometimes do this?

I will post pick when white lights come on. If you look at my rocks they look algae free but with a brownish tint. Definitely not diatoms because they don't brush off.

how old and the pics will help.

 

[fernalfer]

Tank 7 months old pics to come when lights are brightest

 

[twilliard]

Waiting for pics

 

[fernalfer]

Waiting for pics

here they are. You can see on one where the emerald crab was scraping it off. It is a hard brownish coating.

 

[twilliard]

And this is hard in structure?
from the picture it looks to by cyanobacteria on the sand

 

[fernalfer]

And this is hard in structure?
from the picture it looks to by cyanobacteria on the sand

yes there is a few spots of cyano and a little left on one of the rocks by my frogspawn. It was bad before but through constant water changes. reduced feeding and lighting schedule it has pretty much gone away. The brown stuff is hard in structure. I have to scrape it off.

 

[fernalfer]

took a picture turning up the whites some more:

 

[twilliard]

took a picture turning up the whites some more:

From what I can tell I ee a normal rock structure. The disliked color may possibly be coralline

 

[fernalfer]

also on the glass towards the sand i have brownish algae that does not come off with my scraper. and the i also have the algae on the glass that come back around every 6-7 days after cleaning but the hard stuff stays need a credit card or razor to try and get off.

whats the difference between the two

 

[twilliard]

also on the glass towards the sand i have brownish algae that does not come off with my scraper. and the i also have the algae on the glass that come back around every 6-7 days after cleaning but the hard stuff stays need a credit card or razor to try and get off.

whats the difference between the two

without examination under the scope it is hard to say what you have.

 

[saltyfilmfolks]

also on the glass towards the sand i have brownish algae that does not come off with my scraper. and the i also have the algae on the glass that come back around every 6-7 days after cleaning but the hard stuff stays need a credit card or razor to try and get off.

whats the difference between the two

without examination under the scope it is hard to say what you have.

it is possible its a weird coralline or more calcareous algae. In the first year of my tank i had some dark greens and light ones too.
sorry but the colors in the photos are pretty hard to make out.