Looks like an anemone?

[airedwin]

Not sure what this is, I haven't added anything new to my tank in a while

 

[bradleym]

Pseudocorynactis, AKA ball anemone. Most people consider them harmless.

 

[airedwin]

Thank you

 

[Cthulukelele]

They're pretty and reproduce less quickly than aiptasia. They can be a bit invasive though so if you don't like them I'd kill it. It'll spread a bit. Nothing like aiptasia or majanos though

 

[airedwin]

They're pretty and reproduce less quickly than aiptasia. They can be a bit invasive though so if you don't like them I'd kill it. It'll spread a bit. Nothing like aiptasia or majanos though

Thanks, I have no idea where they came from

 

[Cthulukelele]

Thanks, I have no idea where they came from

They're one of those unkillable things that just show up. The babies are tiny and can retract into the smallest of spaces, and they're immensely hardy. My personal opinion is they're a keeper. They tend to not bother nearby things in my experience and they're very cool looking. Not a very strong sting and don't really get much larger than a nickel and honestly usually stay more dime sized. They also seem to like the bottom of the tank and lower light areas. Fun fact they're actually a coral and not an anemone. I'm not even sure they have nematocysts