I believe that’s a type of invasive sponge. Very common in reef tanks with low light and high nutrients. Best way to get rid of it is to scrape it off!I have a white gelatinous substance growing from my rocks. Also, when I went to clean it off, I found circular tentacles looking things curled up in most of them were within an inch long, but there was one large one that was over an inch and thick. It look like squid, octopus arms, or even a starfish arm.
Cryptic sponge. Peel off yes, but do it in a container of tank water as it can release toxins.I have a white gelatinous substance growing from my rocks. Also, when I went to clean it off, I found circular tentacles looking things curled up in most of them were within an inch long, but there was one large one that was over an inch and thick. It look like squid, octopus arms, or even a starfish arm.
