What are these sponges on the bottom of my trachy?

[CampAquarium]

I recently went through my corals and cleaned them up- removed algae, vermitid snails, etc. When I turned over my trachy, I found what looks like 3 different types of sponges. One beige, one yellow, and one pinkish. I haven't noticed these anywhere else in the tank. Any ideas what they might each be, and are any of them harmful/things I should scrape off?

 

[ISpeakForTheSeas]

Sponge ID can be particularly difficult (see the quote below), but - as a general rule of thumb - unless a sponge is growing wildly out of control or it's growing over and smothering corals, sponges are harmless filter feeders. So, there's no need to worry about these guys (particularly since they're probably cryptic sponges and unlikely to compete with corals for space to grow in the light).

Pineapple sponges are from the genus Sycon - The more common pineapple sponges in our tanks can pretty easily be ID’ed by sight (short, round, spiky/fuzzy, has a little spiky crown/funnel looking thing around the opening). Some other pineapple sponge species are much harder to differentiate, and - like many (likely most) sponge species alive - may require microscopic examination and/or DNA testing to actually ID accurately. These sponges in the pics are fuzzy, but they lack the typical “pineapple crown” around the opening, so, they might be pineapple sponges or they might not.

Personally, I wouldn’t feel comfortable giving an ID beyond just saying they’re sponges, as these ones just don’t have enough obviously unique characteristics that I can see to ID from.

Anyway, here’s a good Sponge ID resource for anyone who’s interested- as mentioned, though, sometimes DNA is the best indicator for telling sponges apart:

https://www.fao.org/3/i7773e/i7773e.pdf

And, here’s a decent example of why sponge ID by non-microscopic sight is not always reliable:

https://www.researchgate.net/figure/A-G-Live-specimens-of-Lissodendoryx-species-illustrating-variations-in-shape-and_fig6_248716402

 

[EeyoreIsMySpiritAnimal]

I recently went through my corals and cleaned them up- removed algae, vermitid snails, etc. When I turned over my trachy, I found what looks like 3 different types of sponges. One beige, one yellow, and one pinkish. I haven't noticed these anywhere else in the tank. Any ideas what they might each be, and are any of them harmful/things I should scrape off?

If that is out of the tank they're dead sponges now