What are these?

[Double J]

Just noticed these on the front glass(acrylic). I just removed all the fish on Sunday, so maybe someone was eating them before?

 

[Maritimer]

Probably - an if you have any wrasses, almost certainly!

They're munnid isopods, unless I miss my guess. Harmless members of your cleanup crew, and tasty snacks for any fish who'll feed from the substrate.

Also, moderately prolific . . . though not really to pest proportions.

~Bruce

 

[Double J]

Thanks, yep googled it and looks right, probably because of the outbreak of hair algae. And yes I had a six line wrasse in there.