Help asap what is this??

[Makubex]

Just saw it this morning

 

[Cell]

Bubble algae aka valonia.

 

[Sharkbait19]

Nice big colony of bubble algae.
Emerald crabs eat it.
Manual removal works but is tricky to keep it from spreading that way.

 

[Makubex]

Is it harmful?

 

[vetteguy53081]

Not harmful and should be rid of to prevent further growth. You can use:

Liquid vibrant which works well with bubblr algae. Leave white lights off when using this product

Foxface rabbit fish - which should but can turn on coral therafter

Emerald crabs - Which I simply do not trust

DO NOT POP THEM AS SPORES can be released and create new ones

 

[Jdadams]

It’s just bubble algae. It can be managed. But if left unmanaged it will spread like wildfire. You can get emerald crabs but those are hit or miss though and they have been know to pick at corals. Manual removable and Vibrant works but it takes patience

 

[MaxTremors]

Is it harmful?

It’s not harmful per se, but it spreads quickly. There’s also an aiptasia next to it. To get rid of it, it’s best to pull the rock out and carefully pull them off/scrub with a toothbrush. Despite the age old assertion that they release spores when you pop them, it’s just not true, the issue is that when popped, if any little piece of it gets away, it’ll grow into a new one wherever it lands, but they are not filled with ‘spores’. So, take them out, pull/scrub them off and then rinse the rock off thoroughly.

 

[HeyLookItsCaps]

It’s considered one of the “uglies”. Like hair algae/cyano/aiptasia