help! what are these

[stephensturman]

they are white and round very small all over my glass and it looks like they have legs all around them. cant get a good picture sorry. are they good?

 

[popoetr]

Might be medusa something, I forgot the full name but the first part is medusa

 

[popoetr]

hydroid medusa

 

[graveyardworm]

Sounds like common little isopods. Do they scurry around?