Hello! So to start this off, this is my first post on the forum so I apologize if whatever this is has already been identified. That being said, I've recently started my first saltwater tank and it's just now starting to mature. Over the past few weeks, I've noticed these critters on my live rock and on the glass near the heater (I've attached images.) I'm assuming they came in from my zoas that I bought ~2 months ago (from a trustworthy LFS), but I don't have any other ideas as to where it came from. All fish and corals seem to be fine and water parameters are good. They don't seem to be causing any issues, but they do seem to be multiplying over the past few weeks. If possible can someone ID these for me and let me know the best course of action to get rid of them, I would eternally grateful. Like I said, I'm pretty new to saltwater stuff so it's definitely kind of strange to see random, unidentifiable creatures appearing in your tank! Thanks!
(Also, I can turn on the white lights and get some more pictures if needed)
(Also, I can turn on the white lights and get some more pictures if needed)