Critter ID??!!

[FattyMmatty001]

I turned on my flash tonight to see these flat kinda pod looking things.
•i noticed they don’t swim at all, they stick to this single rock. They crawl/glide on the rock. BTW this rock does have a colony of palythoas I caught one in a syringe i hope you can see the pictures well.

 

[TheSheff]

That sounds a lot like flatworms to me. I just dealt with an infestation of red planaria flatworms. Fix the issue before it gets bad is all I can say!