What are these hitch hikers?

[James044]

About a week or two ago I saw about 5 of these in my tank and took 1 to my LFS to ID it, they said that it was sea spiders but im not so sure, now there must be at least 50 or so of them.
What do you think they could be and could they cause harm to fish?
At the minute there are no fish in the tank.

 

[Magickiwi]

Could they be Fleas?

 

[James044]

I dont know they dont move or anything they just stay stuck to the glass

 

[AquaRick]

Looks like hydroids. I've seen that type early on in tanks and have gone away over time. Have they been multiplying?

 

[AbsoluteFaye]

Definitely hydroids. They'll die off. I had hundreds when I set up my newer tank. Now I have none.

 

[James044]

Thanks it does look like hydroids, I googled it and a pic of the exact same thing i have came up
Glad i know what this is now

 

[James044]

Does anyone know of any fish or critters that will get rid of these?

 

[James044]

Does anyone know of any fish or critter that will get rid of these?

 

[mr_X]

Just like Faye said, they will go away on their own. Nothing to worry about.