What is this?

[Imbarrie]

These are growing in the fuge section of my sump. There is low flow and they are growing from the rocks.
Some kind of nem?

 

[thirty6]

Some type of hydroid maybe

 

[House of Laughter]

I would say aptasia

House

 

[al0ha]

ball anemone

 

[rookie07]

ball anemone

+1
Not an actual anemone, fyi

 

[House of Laughter]

OK ball anemone - = pest

House

 

[Imbarrie]

They are in my fuge, dont know where they came from but I will see what happens with them.
After Googling them some people say they are pests and some say leave them alone.
As long as they stay in my fuge I think they are interesting.

 

[rookie07]

I have not notice these bothering any corals. They generally grow in shady areas where coral does not grow.

 

[Rob&Gab]

ide say get rid of it so it wont spread and be a pain to get rid of.

 

[KathyC]

It won't bother anything and they don't tend to multiply. I had one for years in the shady corner of one of my tanks. An interesting addition.
As Rookie mentioned - nothing else wants to grow where they live anyway!