Mysterious growth on my purple tip elegance coral

[aquabot]

I've been observing these unusual orange "spikes" protruding from my Aussie elegance over the past couple of days. Never seen anything like this before, and I'm stumped. I did notice a slight increase in my PO4 levels lately, up to 0.04 from zero, and I've been dealing with some GHA growth. Could this be causing some kind of reaction in the coral, perhaps?

[zenoxa]

It could be a type of algae or sponge that's taken hold on the coral's skeleton. Now that conditions are favorable, it's starting to grow more noticeably. In my opinion, it's likely harmless, but if you're not a fan of its appearance, you should be able to remove it manually with your fingers, as it should come off relatively easily.

[aquabot]

I'm inclined to agree, it does resemble a sponge. The appearance is quite unusual, and I'm being cautious as this is my first experience with an Aussie elegance. I want to confirm whether these growths are a typical occurrence or something I should be concerned about.