The micro bubbles are fine and won't affect your fish. Just swim near an exposed reef and you will see tons of them with no adverse affects to the marine enviroment.
It's a build up of CO that will cause a problem but if you have good water movement and a skimmer then that won't be a problem.
I'm thinking he was affected by the flatworm treatment.
Keep changing the water and hopefuly he will fully reciver.
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250 gal display tank plumbed directly to my wallet
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