Jellyfish?

[timmyrules]

Hi, I was looking at my tank and I noticed these two little things on the surface of the water that looked/moved kinda like jellyfish….does anyone know what they are?
(Please ignore my tank, it’s over grown with algae. I just got home from vacation.) I would attach a video, but I don’t know how.

 

[ryanjohn1]

Hydroid

 

[timmyrules]

Hydroid

What is that?

 

[ryanjohn1]

What is that?

Look it up my friend

 

[timmyrules]

How did they end up in my tank if I haven’t added anything?

 

[PharmrJohn]

Typical hitchhikers, man. They find a way in on something. Live rock would be my best guess.

 

[DangerDave]

Medusa stage hydroids. I had them on my display build even though I started with dry rock. They just seem to happen. They go away just as quick and mysteriously....

 

[dodojojo]

Hi, I was looking at my tank and I noticed these two little things on the surface of the water that looked/moved kinda like jellyfish….does anyone know what they are?
(Please ignore my tank, it’s over grown with algae. I just got home from vacation.) I would attach a video, but I don’t know how.

Could also be a baby Cassiopeia! The striping is my clue for that. Some jellyfish polyps have the ability to form podocysts and hide out on lots of stuff (usually live rock) and then re-emerge into polyps when water conditions are right.