tiny jellyfish in sump

[hrdneglcry]

I have what appear to be tiny jellyfish in my sump. last week there was one. Now there are many. Anyone have any experience with this?

 

[Peter C]

Yep looks like jelly ephyra! Hard to tell what species without looking under a scope. Chances are they will die out before making it to the medusa phase unless your water is chalked full of rotifers, baby brine, and copepods. Not sure if you bought any live rock in the past but I would assume a polyp came in on a piece of rock and some slight change in tank conditions caused the polyp to strobilate. Likely nothing to be concerned about as long as they don't start showing up in mass and making it to the medusa stage.

 

[hrdneglcry]

Thank you. On the top of the water in the same part of the sump I have tiny red dots that are moving. Any idea what they are?

 

[Peter C]

I don't think I could hazard a guess without a microscope picture. How are they moving?

 

[hrdneglcry]

They seem to kind of go circular. Like a very small oribit. Some swim forward or back but not far from the surface. Very tiny and red. Can see anything but a dot. Will
try magnifying glass. Just hoping they aren't insect larva. I have gnats breeding in my tanks. But these are small. I think they are marine.

 

[Peter C]

They seem to kind of go circular. Like a very small oribit. Some swim forward or back but not far from the surface. Very tiny and red. Can see anything but a dot. Will
try magnifying glass. Just hoping they aren't insect larva. I have gnats breeding in my tanks. But these are small. I think they are marine.

Hmm yeah hard to tell. Let me know if you get a microscope picture or close up.