Black Algae?

[fishkeeprian]

Hello,

Any ideas what this black algae is? When you clean it with a brush hit turns into a powder. It returns in the same spots after about a week or so..

 

[mcgyvr]

Please take a picture with the blue lights off or way down...Its probably cyano..all the blue light is just distorting the color

 

[fishkeeprian]

Please take a picture with the blue lights off or way down...Its probably cyano..all the blue light is just distorting the color

Here's a pic under whites. Still looks black.

https://www.dropbox.com/s/vsyrjdy2q2pvvb9/20190502_173332.jpg?dl=0

 

[D-Nak]

Are you sure it's algae? I kinda looks like a sponge. If it's a sponge it's harmless. Coralline algae may out compete it for space -- in other words it may go away on its own.

 

[fishkeeprian]

Are you sure it's algae? I kinda looks like a sponge. If it's a sponge it's harmless. Coralline algae may out compete it for space -- in other words it may go away on its own.

Don't think it's a sponge it's not got that texture when you brush it off it breaks up into little bits like wet kitchen roll.

 

[mcgyvr]

Looks like cyano..
It can be various colors.. Often red/maroon but can be green/black,etc...

Treat as per typical cyano issue..
Siphon it out then go 3 day lights out and then siphon again.. Repeat as needed every other week or so
Or Chemiclean/red slime remover or a few other commonly suggested approaches.. (More flow.. Look into phosphate issues.. More water changes,etc...)

 

[D-Nak]

When you siphon it, does is freely come off the rock? If so, then I agree it's cyano. And as mcgyver points out, Chemiclean or other cyano remover will do the trick.

 

[fishkeeprian]

When you siphon it, does is freely come off the rock? If so, then I agree it's cyano. And as mcgyver points out, Chemiclean or other cyano remover will do the trick.

:eek2:

It cant be blown off with a Turkey blaster it needs to be removed with a tooth brush. It doesnt take alot of pressure to remove from rock but just blasting it doesnt remove it. It usually has grown back within two days of removing. Its spreading.

 

[fishkeeprian]

I don't have a nutrient problem.

Nitrates at 5ppm and phosphates at 0.06 no other algae issues what so ever.

 

[reefgeezer]

I don't have a nutrient problem.

Nitrates at 5ppm and phosphates at 0.06 no other algae issues what so ever.

It is probably Cyano and it doesn't need available N&P to grow. It shows up when nutrients are low in a lot of tanks. There may be some local organic buildup in the spot where it keeps growing. It gets its N&P from those organic compounds. If you can remove the rock and clean the spot with some peroxide it might solve your problem.

As others have said though, it will probably go away on its own. I'd keep removing it to export the nutrients bound in it until it disappears.

 

[PCguy21]

Dump some chemi clean in there for 5 days and itll never come back.. at least mine didnt