What is this "red" thing?

[vng]

Hello

I found this "red" thing in my refugium. Can some one let me know what is this? Is this good or bad for my tank?

Thanks

 

[seasno]

Looks like a macro algae.....lots of folks intentionally grow macro in their refugiums as a means of nutrient export.

 

[Nikkoli110]

I had some of that algae come in on a small rock, and now it is all over my tank. I hate it. Some people like it and say it looks nice, but I hate it. It grows on every rock in my tank now. And then it will fall off and roll around my sand bed, or get sucked up and stuck to one of the powerhead intakes.