Whats on my chaeto?

[Treenk]

I have no idea what this stuff is growing on the chaeto but I keep pulling those chunks off and it keeps coming back. Its in top left of the first picture and then I moved it down to the right on the second.

 

[Idoc]

Looks like cyano. I was getting it on the top of my chaeto as well previously.

 

[Treenk]

I was leaning towards that too thank you

 

[Thaxxx]

I get the same on mine a lot. Never in DT. You always see that low flow is one cause of cyano. I have very heavy flow in my fuge, tumbling my cheato. Makes no difference.