At first I thought these were eggs, but I can't think of anything in my tank that would lay eggs like this and I have seen more appearing around the tank. I am guessing it must be a sponge.
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
I think you are right about the tunicates. Photos online show many of them having the same geometric hexagon, pentagon etc. shapes these do. Thanks for the help!Either sponges or colonial tunicates; I'm leaning toward colonial tunicates, but I'm not sure on that at this point.
Either way, they're harmless filter feeders that may become invasive; so I'd keep an eye them and remove them as needed.