Yea those are all good answers, but the sad part about any of these pests is that once you have them, you have them forever. The aiptasia get in your plumbing and live in there, and bubble algae always finds cracks and crannies to live in where fish or emerald crabs can't get them.
I've got bubble algae as well. It came in on a plug that didn't have any algae when I bought it. Totally blank, just the coral on a clean plug. After a week in my tank, it sprouted up with bubbles everywhere. Even after removing them, they grew on the plug, and eventually spread.
Aiptasia if you quickly nuke them with kalk they won't spread, but once they do spread, or if you are careful with their removal and not scorched earth, they'll spread.
That's one of the hard parts of a mature nano tank, you can't use the biological controls of large tanks for bubble algae or even aiptasia long term.
In my old 120g tank, my sailfin tang ate the bubble algae, and peppermint shrimp ate aiptasia. But in a nano, it's a lot harder.
I think the only way to really avoid those algae and aiptasia pests are to remove frags from plugs entirely, as well as any dead flesh that could harbor either. Too late now, sorry, and also still nothing is guaranteed.
At least you don't also have this stupid gsp problem I have growing everywhere (again).
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